TWENTY FIRST CENTURY SCIENCE SUITE
GCSE ADDITIONAL SCIENCE AACCREDITED SPECIFICATION
J242VERSION 2
MAY 2012
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WELCOME TO GCSE SCIENCESTHOUSANDS OF TEACHERS ALREADY UNLEASH THE JOY OF SCIENCE WITH OCR.
A FEW GOOD REASONS TO WORK WITH OCR • You can enjoy the freedom and excitement of teaching
science qualifications which have been developed to help you inspire students of all abilities.
• We’ve built specifications with you in mind, using a clear and easy-to-understand format, making them straightforward for you to deliver.
• Our clear and sensible assessment approach means that exam papers and requirements are clearly presented and sensibly structured for you and your students.
• Pathways for choice – we have the broadest range of science qualifications and our GCSEs provide an ideal foundation for students to progress to more advanced studies and science-related careers.
• Working in partnership to support you – together with teachers we’ve developed a range of practical help and support to save you time. We provide everything you need to teach our specifications with confidence and ensure your students get as much as possible from our qualifications.
• A personal service – as well as providing you with lots of support resources, we’re also here to help you with specialist advice, guidance and support for those times when you simply need a more individual service.
DON’T FORGET – you can download a
copy of this specification and all our support materials at
www.ocr.org.uk/gcse2012
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SPECIALIST ADVICE: Phone: 01223 553998
Email: [email protected]
Online: http://answers.ocr.org.uk
Fax: 01223 552627
Post: Customer Contact Centre, OCR, Progress House, Westwood
Business Park, Coventry CV4 8JQ
iii
Our essential FREE support includes:
Materials• Specimen assessment materials and mark schemes• Guide to controlled assessment• Sample controlled assessment material• Exemplar candidate work• Marking commentaries• Teacher’s handbook• Sample schemes of work and lesson plans• Frequently asked questions• Past papers.
You can access all of our support at: www.ocr.org.uk/gcse2012
Science CommunityJoin our social network at www.social.ocr.org.uk where you can start discussions, ask questions and upload resources.
Services• Answers @ OCR – a web based service where
you can browse hot topics, FAQs or e-mail us with your questions. Visit http://answers.ocr.org.uk
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Endorsed publisher partner materialsWe’re working closely with our publisher partner Oxford University Press to ensure effective delivery of endorsed materials when you need them. Find out more at: www.twentyfirstcenturyscience.org
SUPPORTING YOU ALL THE WAY
Our aim is to help you at every stage and we work in close consultation with teachers and other experts, to provide a practical package of high quality resources and support.
Our support materials are designed to save you time while you prepare for and teach our new specifications. In response to what you have told us we are offering detailed guidance on key topics and controlled assessment.
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TWENTY FIRST CENTURY SCIENCE SUITEScience today – for scientists of tomorrow
Explore the science that underpins day-to-day life. Enthuse and motivate students using a mix of teaching strategies.
Our Twenty First Century Science suite:
• is engaging to study and motivating for you to teach
• will help your students engage with the course rather than just study it
• gives you the flexibility to choose a delivery style to engage students.
KEY FEATURES• How Science Works, fully integrated into teaching and
assessment.
• An ideal foundation for students to progress to more-advanced studies and science-related careers.
• A well regarded and proven concept led teaching approach to science.
or
POSSIBLE GCSE COMBINATIONS
GCSE TWENTY FIRST CENTURY
SCIENCE A*
GCSE TWENTY FIRST CENTURY
ADDITIONAL SCIENCE A
OCR GCSE ADDITIONAL
APPLIED SCIENCE
GCSE ENVIRONMENTAL AND LAND-BASED
SCIENCE
GCSE TWENTY FIRST CENTURY
BIOLOGY A
or
or
or GCSE TWENTY FIRST CENTURY
CHEMISTRY A
GCSE TWENTY FIRST CENTURY
PHYSICS A
Either
* Entry Level Science can lead to GCSE Twenty First Century Science A
v
GCSE ADDITIONAL SCIENCE AKEY FEATURES GCSE Additional Science A uses different contexts to relate science concepts to their applications. Focusing on scientific explanations and models, it gives students an insight into how scientists help develop our understanding of ourselves and the world we live in. GCSE Additional Science A provides distinctive and relevant experience for learners who wish to progress to Level 3 qualifications.
UNIT A162 (BIOLOGY A)Module B4: The processes of lifeModule B5: Growth and developmentModule B6: Brain and mind
UNIT A172 (CHEMISTRY A)Module C4: Chemical patternsModule C5: Chemicals of the natural environmentModule C6: Chemical synthesis
UNIT A182 (PHYSICS A)Module P4: Explaining motionModule P5: Electric circuitsModule P6: Radioactive materials
60 marks1 hour written paper
60 marks1 hour written paper
60 marks1 hour written paper
25% of total GCSE
Three written exams, assessed externally by OCR, each of which:
• isofferedinFoundationandHigher Tiers
• usesbothobjectivestyleandfree response questions (there is no choice of questions)
• assessesthequalityofwrittencommunication.25%
of total GCSE
25% of total GCSE
UNIT A154 (ADDITIONAL SCIENCE A)Controlled assessment
64 marksApprox 6–7 hours 25%
of total GCSE
Comprises a Practical Investigation from a choice set by OCR.
Assessed by teachers, internally standardised and externally moderated by OCR.
Assesses the quality of written communication.
COURSE OVERVIEW ASSESSMENT OVERVIEW
PROGRESSION PATHWAYS IN SCIENCE
vi
Science A Levels
IGCSE
KS4 Vocational Science
Subjects
KS3 Curriculum
This could be a progression route along a particular curriculum pathway. (Stage, not age pathways)
This could be a progression route however students would require additional support.
* Offered asScience, Additional Science, Biology, Chemistry and Physics.
Alternative qualification options
1 ©OCR2012GCSEAdditionalScienceA
OCR GCSE in Additional Science A J242
QN600/1355/2
2 ©OCR2012GCSEAdditionalScienceA
Contents
2 Introduction to GCSE Additional Science A 5
1 Introduction to the Twenty First Century Science suite 4
3 Content of GCSE Additional Science A 8
4 Assessment of GCSE Additional Science A 79
5 Controlled assessment in GCSE Additional Science A 84
6 Support for GCSE Additional Science A 97
2.1 OverviewofGCSEAdditionalScienceA 5
2.2 WhatisnewinGCSEAdditionalScienceA? 6
2.3 Guidedlearninghours 6
2.4 Aimsandlearningoutcomes 7
2.5 Priorlearning 7
3.1 Summaryofcontent 8
3.2 Layoutofspecificationcontent 10
3.3 IdeasaboutScience 11
3.4 SummaryofUnitA162:Biology AModules B4, B5, B6 21
3.5 SummaryofUnitA172:Chemistry A Modules C4, C5, C6 39
3.6 SummaryofUnitA182:Physics A Modules P4, P5, P6 59
4.1 OverviewoftheassessmentinGCSEAdditionalScienceA 79
4.2 Tiers 80
4.3 Assessmentobjectives(AOs) 80
4.4 Gradingandawardinggrades 81
4.5 Gradedescriptions 82
4.6 Qualityofwrittencommunication 83
5.1 Introductiontocontrolledassessmenttasks 84
5.2 Natureofcontrolledassessmenttasks 84
5.3 Planningandmanagingcontrolledassessment 86
5.4 Markingandmoderatingcontrolledassessment 88
5.5 Internalstandardisation 95
5.6 Submittingmarksandauthentication 95
5.7 Submittingsamplesofcandidatework 95
5.8 Externalmoderation 96
6.1 FreesupportandtrainingfromOCR 97
6.2 OCRendorsedresources 97
6.3 Training 99
6.4 OCRsupportservices 99
3 ©OCR2012GCSEAdditionalScienceA
Contents
Appendix B: Mathematics skills for GCSE science qualifications 110
Appendix C: Physical quantities and units 111
Appendix D: Health and safety 113
Appendix E: Electrical symbols 114
Appendix F: Periodic table 115
Appendix G: Qualitative analysis 116
Appendix H: Hazard labelling 117
7 Equality and inclusion in GCSE Additional Science A 100
8 Administration of GCSE Additional Science A 102
9 Other information about GCSE Additional Science A 105
7.1 EqualityActinformationrelatingtoGCSEAdditionalScienceA 100
7.2 Arrangementsforcandidateswithparticularrequirements 101(includingSpecialConsideration)
8.1 Availabilityofassessmentfrom2014 102
8.2 Certificationrules 102
8.3 Rulesforre-takingaqualification 102
8.4 Makingentries 103
8.5 Enquiriesaboutresults 104
8.6 Prohibitedqualificationsandclassificationcode 104
9.1 Overlapwithotherqualifications 105
9.2 Progressionfromthisqualification 105
9.3 Avoidanceofbias 105
9.4 Regulatoryrequirements 105
9.5 Language 105
9.6 Spiritual,moral,ethical,social,legislative,economicandculturalissues 106
9.7 Sustainabledevelopment,healthandsafetyconsiderationsandEuropeandevelopments,consistentwithinternationalagreements 106
9.8 KeySkills 107
9.9 ICT 107
9.10 Citizenship 107
Appendix A: Guidance for the production of electronic 108 controlled assessment
4 ©OCR2012GCSEAdditionalScienceA
1 Introduction to the Twenty First Century Science suite
TheTwentyFirstCenturySciencesuitecomprisesfivespecificationswhichshareasimilarapproachtoteachingandlearning,utilisecommonmaterials,useaconsistentstyleofexaminationquestionsandhaveacommonapproachtoskillsassessment.
Thequalificationsavailableaspartofthissuiteare:
• GCSEScienceA
• GCSEAdditionalScienceA
• GCSEBiologyA
• GCSEChemistryA
• GCSEPhysicsA.
GCSE Science A (J241) whichemphasisesscientificliteracy–theknowledgeandunderstandingwhichcandidatesneedtoengage,asinformedcitizens,withscience-basedissues.Aswithothercoursesinthesuite,thisqualificationusescontemporary,relevantcontextsofinteresttocandidates,whichcanbeapproachedthrougharangeofteachingandlearningapproaches.
GCSE Additional Science A (J242)
whichisaconcept-ledcoursedevelopedtomeettheneedsofcandidatesseekingadeeperunderstandingofbasicscientificideas.Thecoursefocusesonscientificexplanationsandmodels,andgivescandidatesaninsightintohowscientistsdevelopscientificunderstandingofourselvesandtheworldweinhabit.
GCSE Biology A (J243) eachofwhichprovidesanopportunityforfurtherdevelopinganunderstandingofscienceexplanations,howscienceworksandthestudyofelementsofappliedscience,withparticularrelevancetoprofessionalscientists.
GCSE Chemistry A (J244)
GCSE Physics A (J245)
Thesuiteemphasisesexplanations,theoriesandmodellinginsciencealongwiththeimplicationsofscienceforsociety.Strongemphasisisplacedontheactiveinvolvementofcandidatesinthelearningprocessandeachspecificationencouragesawiderangeofteachingandlearningactivities.
ThesuiteissupportedbytheNuffieldFoundationCurriculumProgrammeandtheUniversityofYorkScienceEducationGroup,andbyresourcespublishedbyOxfordUniversityPress.
Inaddition,anAdditionalAppliedSciencecourse(J251)isavailable.ThiscanbeusedinconjunctionwithScienceAasanalternativeroutetotwoscienceGCSEs,forcandidatesnotfollowingGCSEAdditionalScienceA.
5 ©OCR2012GCSEAdditionalScienceA
Introduction to GCSE Additional Science A 2
2.1 Overview of GCSE Additional Science A
Unit A162: Biology A Modules B4, B5, B6
Unit A172: Chemistry A Modules C4, C5, C6
Unit A182: Physics A Modules P4, P5, P6
Unit A154: Additional Science A Controlled assessment
ThisisatieredunitofferedinFoundationandHigherTiers.
Writtenpaper1hour60marks25%ofthequalification
Candidatesanswerallquestions.Theunitusesbothobjectivestyleandfreeresponsequestions.
ThisisatieredunitofferedinFoundationandHigherTiers.
Writtenpaper1hour60marks25%ofthequalification
Candidatesanswerallquestions.Theunitusesbothobjectivestyleandfreeresponsequestions.
ThisisatieredunitofferedinFoundationandHigherTiers.
Writtenpaper1hour60marks25%ofthequalification
Candidatesanswerallquestions.Theunitusesbothobjectivestyleandfreeresponsequestions.
+
+
+
Thisunitisnottiered. ControlledassessmentApproximately4.5–6hours64marks25%ofthequalification
6 ©OCR2012GCSEAdditionalScienceA
2
2.2 What is new in GCSE Additional Science A?
2.3 Guided learning hours
GCSEAdditionalScienceArequires120–140guidedlearninghoursintotal.
What stays the same? What changes?
Structure • Fourunitsofassessment,comprisingthreeexternallyassessedunitsandoneinternallyassessedunit.
• Allfourunitshaveequalweightingsof25%.
• Externallyassessedunitsaretiered–FoundationandHigherTier.
• Internallyassessedunitiscontrolledassessment.
• Thecoursecanonlybeassessedaslinear.
• Onlyoneroutetocertification.
Content • Contentisdividedintoninemodules.• Nochangestomodulecontent.
• AlloftheIdeasaboutScienceprovidetheunderlyingcontextforallmodulesandunitsofassessment.
Assessment • Modulesexternallyassessedwithinwrittenexaminationpapers.
• Modulesassessedinparticularunitsareunchanged.
• ChoiceofcontrolledassessmenttaskssetbyOCRvalidforentryinasingleexaminationseriesonly.
• Controlledassessmentunitworth25%andavailableinJuneseriesonly.
• ControlledassessmentunitconsistsofaCaseStudyandPracticalDataAnalysis.
• Qualityofwrittencommunication(QWC)assessedinallunits.
• Externallyassessedpaperseach1hourlong,withatotalof60marksdividedbetweenobjective(upto40%)andfree-responsestylequestions.
• New100%terminalruleappliestoscienceGCSEs.
• Nomixedsciencewrittenpapers–writtenpaperscorrespondtobiology,chemistryandphysics.
• AlloftheIdeasaboutSciencemaybeassessedinallunits.
• Allunits,includingwrittenpapers,availableforassessmentinJuneseriesonly.
• CertificationinthesameseriesinTwentyFirstCenturyScienceAGCSEandTwentyFirstCenturyBiologyA,ChemistryAorPhysicsAGCSEsisnolongerpossible.
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2.4 Aims and learning outcomes
2.5 Prior learning
GCSEspecificationsinAdditionalScienceshouldencouragelearnerstodeveloptheirknowledgeabouttheliving,materialandphysicalworldsandprovideinsightinto,andexperienceof,howscienceworks.Theyshouldenablelearnerstoengagewithscienceandtomakeinformeddecisionsaboutfurtherstudyinscienceandrelatedsubjectsandaboutcareerchoices.
Theaimsofthisspecificationaretoenablecandidatesto:
• developtheirknowledgeandunderstandingofthematerial,physicalandlivingworlds
• developtheirunderstandingoftheeffectsofscienceonsociety
• developanunderstandingoftheimportanceofscaleinscience
• developandapplytheirknowledgeandunderstandingofthenatureofscienceandofthescientificprocess
• developtheirunderstandingoftherelationshipsbetweenhypotheses,evidence,theoriesandexplanations
• developtheirawarenessofriskandtheabilitytoassesspotentialriskinthecontextofpotentialbenefits
• developandapplytheirobservational,practical,modelling,enquiryandproblem-solvingskillsandunderstandinginlaboratory,fieldandotherlearningenvironments
• developtheirabilitytoevaluateclaimsbasedonsciencethroughcriticalanalysisofthemethodology,evidenceandconclusionsbothqualitativelyandquantitatively
• developtheirskillsincommunication,mathematicsandtheuseoftechnologyinscientificcontexts.
CandidatesenteringthiscourseshouldhaveachievedageneraleducationallevelequivalenttoNationalCurriculumLevel3,oranEntry3atEntryLevelwithintheNationalQualificationsFramework.
8 ©OCR2012GCSEAdditionalScienceA
©OCR2012GCSEAdditionalScienceA
9Content of GCSE Additional Science A3
3.1 Summary of content
GCSEAdditionalScienceAcoursecontentgivesemphasisandspacetofundamentalideasinthesciences,ensuresthatappropriateskillsaredevelopedinpreparationforfurtherstudy,andprovidesastimulatingbridgetoadvancedlevelsinscience.Theemphasisofthecourseison‘scienceforthescientist’andthoseaspectsof‘HowScienceWorks’thatrelatetotheprocessofscience.
Amoduledefinestherequiredteachingandlearningoutcomes.
Thespecificationcontentisdisplayedasninemodules.Thetitlesoftheseninemodulesarelistedinthetableonthenextpage.
Eachmoduleisdesignedtobetaughtinapproximatelyhalf a term,in10%ofthecandidates’curriculumtime.
8 ©OCR2012GCSEAdditionalScienceA
©OCR2012GCSEAdditionalScienceA
9
Con
tent
of
GC
SE
Add
itio
nal S
cien
ce A
3
Mod
ule
B4:
The
pro
cess
es o
f life
Mod
ule
B5:
Gro
wth
and
dev
elop
men
tM
odul
e B
6: B
rain
and
min
d
•How
dochem
icalreactionstakeplaceinliving
things?
•How
doplantsmakefood?
•How
dolivingorganism
sobtainenergy?
•How
doorganism
sdevelop?
•How
doesanorganismproducenew
cells?
•How
dogenescontrolgrowthanddevelopment
withinthecell?
•How
doanimalsrespondtochangesintheir
environm
ent?
•How
isinformationpassedthroughthenervous
system
?•
Canreflexresponsesbelearned?
•How
dohumansdevelopmorecomplexbehaviour?
Mod
ule
C4:
Che
mic
al p
atte
rns
Mod
ule
C5:
Che
mic
als
of th
e na
tura
l en
viro
nmen
tM
odul
e C
6: C
hem
ical
syn
thes
is
•Whatarethepatternsinthepropertiesof
elem
ents?
•How
dochem
istsexplainthepatternsinthe
propertiesofelements?
•How
dochem
istsexplainthepropertiesof
compoundsofG
roup1andGroup7elements?
•Whattypesofchemicalsmakeupthe
atmosphere?
•Whatreactionshappeninthehydrosphere?
•WhattypesofchemicalsmakeuptheEarth’s
lithosphere?
•How
canweextractusefulm
etalsfromminerals?
•Chemicalsandwhyweneedthem
.•
Planning,carryingoutandcontrollingachemical
synthesis.
Mod
ule
P4: E
xpla
inin
g m
otio
nM
odul
e P5
: Ele
ctric
circ
uits
Mod
ule
P6: R
adio
activ
e m
ater
ials
•How
canwedescribemotion?
•Whatareforces?
•Whatistheconnectionbetweenforcesand
motion?
•How
canwedescribemotionintermsofenergy
changes?
•Electriccurrent–aflow
ofw
hat?
•Whatdeterminesthesizeofthecurrentinan
electriccircuitandtheenergyittransfers?
•How
doparallelandseriescircuitswork?
•How
ismainselectricityproduced?How
are
voltagesandcurrentsinduced?
•How
doelectricmotorswork?
•Whyaresom
ematerialsradioactive?
•How
canradioactivematerialsbeusedandhandled
safely,includingwastes?
10 ©OCR2012GCSEAdditionalScienceA
Thespecificationcontentisdividedintoninemodulesthat,togetherwiththeIdeasaboutScience(seeSection3.3),areassessedacrossthreewrittenpapers(UnitsA162,A172andA182)andoneunitofcontrolledassessment(UnitA154).
Section3.3describestheIdeasaboutScienceandwhatcandidateswillneedtounderstandandbeabletodo.TheIdeasaboutScienceareassessedacrossallunits.
Sections3.4,3.5and3.6summarisethethreewrittenpaperunits,A162,A172andA182,andtheassociatedcontentthatcanbeassessedwithinthem.Withineachofthesesections,abriefsummaryoftheunitprecedesthedetaileddescriptionofthemodulesthatareassessedwithinthatunit.
Eachmodulestartswithanoverviewthatexplainsthebackgroundtothemoduleandidentifies:
• asummaryofthetopics
• opportunitiesformathematics
• opportunitiesforpracticalwork
• opportunitiesforICT
• examplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopment.
Followingthemoduleoverview,themodulecontentispresentedindetail.
Withinthedetailedcontentofeachmodule,notationsareusedtogiveteachersadditionalinformationabouttheassessment.Thetablebelowsummarisesthesenotations.
3
3.2 Layout of specification content
Notation Explanation
Bold These content statements will only be assessed on Higher Tier papers.
Advisory notes for teachers to clarify depth of coverage required.
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3.3 Ideas about Science
ThespecificationswithintheTwentyFirstCenturySciencesuiteareuniqueinhavinginterpretedandextrapolatedtheprinciplesof‘HowScienceWorks’intoaseriesof‘IdeasaboutScience’.ItisintendedthattheIdeasaboutSciencewillensurestudentsunderstandhowscientificknowledgeisobtained,howitisreportedintheworldoutsidetheclassroom,andtheimpactsofscientificknowledgeonsociety.
GCSEAdditionalScienceAaimstodevelopstudents’understandingoftheIdeasaboutSciencealongsidetheirgrowingunderstandingofscientificideasandexplanationsofthebehaviourofthenaturalworld.
Inordertomakesenseofthescientificideasthatstudentsencounterinlessonsandreadorhearaboutoutsideofschool,theyneedtodevelopanunderstandingofscienceitself–ofhowscientificknowledgeisobtained,thekindsofevidenceandreasoningbehindit,itsstrengthsandlimitations,andhowfarwecanthereforerelyonit.Theyalsoneedopportunitiestoreflectontheimpactsofscientificknowledgeonsociety,andhowwerespondindividuallyandcollectivelytothenewideas,artefactsandprocessesthatsciencemakespossible.
Reportsofscientificclaims,inventionsanddiscoveriesareprolificinthemediaofthetwentyfirstcentury,andanunderstandingoftheIdeasaboutSciencewillensurethatstudentsarewell-equippedtocriticallyevaluatethesciencestoriestheyreadandhear.
Thekindofunderstandingofsciencethatwewouldwishstudentstohavebytheendoftheirschoolscienceeducationmightbesummarisedasfollows:
Why are Ideas about Science important?
How science worksTheaimofscienceistofindexplanationsforthebehaviourofthenaturalworld.Thereisnosingle‘methodofscience’thatleadsautomaticallytoscientificknowledge.Scientistsdo,however,havecharacteristicwaysofworking.Inparticular,datafromobservationsandmeasurementsareofcentralimportance.Alldata,however,havetobeinterpreted,andthisisinfluencedbytheideaswebringtoit.Scientificexplanationsdonot‘emerge’automaticallyfromdata.Proposinganexplanationinvolvescreativethinking.So,itisquitepossible(andmaybequitereasonable)fordifferentpeopletoarriveatdifferentexplanationsforthesamedata.
Causes and effectsScientistsoftenlookforcause-effectexplanations.Thefirststepistoidentifyacorrelationbetweenafactorandanoutcome.Thefactormaythenbethecause,oroneofthecauses,oftheoutcome.Inmanysituationsafactormaynotalwaysleadtotheoutcome,butincreasesthechance(ortherisk)ofithappening.Inordertoclaimthatthefactorcausestheoutcomeweneedtoidentifyaprocessormechanismthatmightaccountfortheobservedcorrelation.
Theories, explanations and predictionsAscientifictheoryisageneralexplanationthatappliestoalargenumberofsituationsorexamples(perhapstoallpossibleones),whichhasbeentestedandusedsuccessfully,andiswidelyacceptedbyscientists.Ascientifictheorymightproposeamodelinvolvingobjects(andtheirbehaviour)thatcannotbeobserveddirectly,toaccountforwhatweobserve.Oritmightdefinequantitiesandwaysofmeasuringthem,andstatesomemathematicalrelationshipsbetweenthem.
Ascientificexplanationofaspecificeventorphenomenonisoftenbasedonapplyingascientifictheory(ortheories)tothesituationinquestion.
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Aproposedscientificexplanation(whetheritisaverygeneralscientifictheoryoramorespecificexplanation)istestedbycomparingpredictionsbasedonitwithobservationsormeasurements.Iftheseagree,itincreasesourconfidencethattheexplanationmightbecorrect.Thiscanneverbeconclusivelyproved,butaccumulatingevidencecanbringustothepointwhereitishardtoimagineanyotherpossibleexplanation.Ifpredictionanddatadisagree,thenoneortheothermustbewrong.Datacanneverbereliedoncompletelybecauseobservationsmaybeincorrectandallmeasurementsaresubjecttouncertainty,arisingfromtheinevitablelimitationsofthemeasuringequipmentorthepersonusingit.Ifwebelievethedataareaccurate,thenthepredictionmustbewrong,loweringourconfidenceintheproposedexplanation.
Science and scientistsThescientificcommunityhasestablishedrobustproceduresfortestingandcheckingtheclaimsofindividualscientists,andreachinganagreedview.Scientistsreporttheirfindingstootherscientistsatconferencesandinpeer-reviewedjournals.Claimsarenotaccepteduntiltheyhavesurvivedthecriticalscrutinyofthescientificcommunity.Insomeareasofenquiry,ithasprovedpossibletoeliminatealltheexplanationswecanthinkofbutone–whichthenbecomestheacceptedexplanation(until,ifever,abetteroneisproposed).
Wherepossible,scientistschoosetostudysimplesituationsinordertogainunderstanding.This,however,canmakeitdifficulttoapplythisunderstandingtocomplex,real-worldsituations.Sotherecanbelegitimatedisagreementsaboutscientificexplanationsofparticularphenomenaorevents,eventhoughthereisnodisputeaboutthefundamentalscientificknowledgeinvolved.
Science and societyTheapplicationofscientificknowledge,innewtechnologies,materialsanddevices,greatlyenhancesourlives,butcanalsohaveunintendedandundesirableside-effects.Oftenweneedtoweighupthebenefitsagainstthedisadvantages–andalsoconsiderwhogainsandwholoses.Anapplicationofsciencemayhavesocial,economicandpoliticalimplications,andsometimesalsoethicalones.Personalandsocialdecisionsrequireanunderstandingofthescienceinvolved,butalsoinvolveknowledgeandvaluesthatgobeyondscience.
WithinthisSectionalloftheIdeasaboutSciencearelistedtogether,inanorderthatshowsclearlyhowtheyrelatetooneanotherandbuilduptheunderstandingofsciencethatwewouldlikestudentstodevelop.
InadditiontothisSection,specificIdeasaboutScienceareidentifiedatthestartofeachmodulewithinthespecification,toindicatethattherearegoodopportunitieswithinthecontentofthemoduletointroduceanddevelopthem.TheOCRschemeofworkforGCSEAdditionalScienceA(publishedseparately)willalsohighlightteachingopportunitiesforspecificIdeasaboutScience.
ThefollowingpagessetoutindetailtheIdeasaboutScienceandwhatcandidatesshouldbeabletodotodemonstratetheirunderstandingofthem.Thestatementsintheleft-handcolumnspecifytheunderstandingscandidatesareexpectedtodevelop;theentriesintheright-handcolumnaresuggestionsaboutsomewaysinwhichevidenceofunderstandingcanbedemonstrated.
How can Ideas about Science be developed in teaching?
What are the Ideas about Science?
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All Ideas about Science can be assessed in all units of assessment.ThosethatwillonlybeassessedinHigherTierpapersareindicatedinbold.
Inordertoassistwithcurriculumplanning,IdeasaboutSciencethatcouldbelinkedtoeachmodulearesuggestedintheoverviewofeachmodule(seeSections3.4,3.5and3.6).Takingallofthemodulestogether,suggestedlinkstoalloftheIdeasaboutScienceareidentifiedinthisway.However,itisnotintendedthatunderstandingandapplicationoftheIdeasaboutScienceshouldbelimitedtoanyparticularcontext,sotheselinksareprovidedassuggestionsonly.ThereisfreedomtodeveloplinksbetweenmodulesandtheIdeasaboutScienceinanyway,providingthatallhavebeencoveredpriortoassessment.
How are Ideas about Science assessed?
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1 Data: their importance and limitationsDataarethestartingpointforscientificenquiry–andthemeansoftestingscientificexplanations.Butdatacanneverbetrustedcompletely,andscientistsneedwaysofevaluatinghowgoodtheirdataare.
Candidates should understand that: A candidate who understands this can, for example:
1.1 • dataarecrucialtoscience.Thesearchforexplanationsstartsfromdata;anddataarecollectedtotestproposedexplanations.
• usedataratherthanopinionifaskedtojustifyanexplanation
• outlinehowaproposedscientificexplanationhasbeen(ormightbe)tested,referringappropriatelytotheroleofdata.
1.2 • wecanneverbesurethatameasurementtellsusthetruevalueofthequantitybeingmeasured.
• suggestreasonswhyagivenmeasurementmaynotbethetruevalueofthequantitybeingmeasured.
1.3 • ifwemakeseveralmeasurementsofanyquantity,thesearelikelytovary.
• suggestreasonswhyseveralmeasurementsofthesamequantitymaygivedifferentvalues
• whenaskedtoevaluatedata,makereferencetoitsrepeatabilityand/or reproducibility.
1.4 • themeanofseveralrepeatmeasurementsisagoodestimateofthetruevalueofthequantitybeingmeasured.
• calculatethemeanofasetofrepeatedmeasurements
• fromasetofrepeatedmeasurementsofaquantity,usethemeanasthebestestimateofthetruevalue
• explainwhyrepeatingmeasurementsleadstoabetterestimateofthequantity.
1.5 • fromasetofrepeatedmeasurementsofaquantity,itispossibletoestimatearangewithinwhichthetruevalueprobablylies.
• fromasetofrepeatedmeasurementsofaquantity,makeasensiblesuggestionabouttherangewithinwhichthetruevalueprobablyliesand explain this
• when discussing the evidence that a quantity measured under two different conditions has (or has not) changed, make appropriate reference both to the difference in means and to the variation within each set of measurements.
1.6 • ifameasurementlieswelloutsidetherangewithinwhichtheothersinasetofrepeatslie,orisoffagraphlineonwhichtheotherslie,thisisasignthatitmaybeincorrect.Ifpossible,itshouldbechecked.Ifnot,itshouldbeusedunlessthereisaspecificreasontodoubtitsaccuracy.
• identifyanyoutliersinasetofdata• treatanoutlierasdataunlessthereisa
reasonfordoubtingitsaccuracy• discuss and defend the decision to
discard or to retain an outlier.
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2 Cause-effect explanationsScientistslookforpatternsindata,asameansofidentifyingcorrelationsthatmightsuggestpossiblecause-effectlinks–forwhichanexplanationmightthenbesought.
Candidates should understand that: A candidate who understands this can, for example:
2.1 • itisoftenusefultothinkaboutprocessesintermsoffactorswhichmayaffectanoutcome(orinputvariableswhichmayaffectanoutcomevariable).
• inagivencontext,identifytheoutcomeandfactorsthatmayaffectit
• inagivencontext,suggesthowanoutcomemightalterwhenafactorischanged.
2.2 • toinvestigatetherelationshipbetweenafactorandanoutcome,itisimportanttocontrolalltheotherfactorswhichwethinkmightaffecttheoutcome(aso-called‘fairtest’).
• identify,inaplanforaninvestigationoftheeffectofafactoronanoutcome,thefactthatotherfactorsarecontrolledasapositivedesignfeature,orthefactthattheyarenotasadesignflaw
• explainwhyitisnecessarytocontrolallthefactorsthatmightaffecttheoutcomeotherthantheonebeinginvestigated.
2.3 • ifanoutcomeoccurswhenaspecificfactorispresent,butdoesnotwhenitisabsent,orifanoutcomevariableincreases(ordecreases)steadilyasaninputvariableincreases,wesaythatthereisacorrelationbetweenthetwo.
• suggestandexplainanexamplefromeverydaylifeofacorrelationbetweenafactorandanoutcome
• identifywhereacorrelationexistswhendataarepresentedastext,asagraph,orinatable.
Examples may include both positive and negative correlations, but candidates will not be expected to know these terms.
2.4 • acorrelationbetweenafactorandanoutcomedoesnotnecessarilymeanthatthefactorcausestheoutcome;bothmight,forexample,becausedbysomeotherfactor.
• usetheideasofcorrelationandcausewhendiscussingdataandshowawarenessthatacorrelationdoesnotnecessarilyindicateacausallink
• identify,andsuggestfromeverydayexperience,examplesofcorrelationsbetweenafactorandanoutcomewherethefactoris(orisnot)aplausiblecauseoftheoutcome
• explainwhyanobservedcorrelationbetweenagivenfactorandoutcomedoesnotnecessarilymeanthatthefactorcausestheoutcome.
2.5 • insomesituations,afactoraltersthechance(orprobability)ofanoutcome,butdoesnotinvariablyleadtoit.Wealsocallthisacorrelation.
• suggestfactorsthatmightincreasethechanceofaparticularoutcomeinagivensituation,butdonotinvariablyleadtoit
• explainwhyindividualcasesdonotprovideconvincingevidencefororagainstacorrelation.
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Candidates should understand that: A candidate who understands this can, for example:
2.6 • toinvestigateaclaimthatafactorincreasesthechance(orprobability)ofanoutcome,scientistscomparesamples(e.g.groupsofpeople)thatarematchedonasmanyotherfactorsaspossible,orarechosenrandomlysothatotherfactorsareequallylikelyinbothsamples.Thelargerthesamples,themoreconfidentwecanbeaboutanyconclusionsdrawn.
• discusswhethergivendatasuggestthatagivenfactordoes/doesnotincreasethechanceofagivenoutcome
• evaluatecriticallythedesignofastudytotestifagivenfactorincreasesthechanceofagivenoutcome,bycommentingonsamplesizeandhowwellthesamplesarematched.
2.7 • even when there is evidence that a factor is correlated with an outcome, scientists are unlikely to accept that it is a cause of the outcome, unless they can think of a plausible mechanism linking the two.
• identify the presence (or absence) of a plausible mechanism as reasonable grounds for accepting (or rejecting) a claim that a factor is a cause of an outcome.
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3 Developing scientific explanationsTheaimofscienceistodevelopgoodexplanationsfornaturalphenomena.Initially,anexplanationisahypothesisthatmightaccountfortheavailabledata.Asmoreevidencebecomesavailable,itmaybecomeanacceptedexplanationortheory.Scientificexplanationsandtheoriesdonot‘emerge’automaticallyfromdata,andcannotbededucedfromthedata.Proposinganexplanationortheoryinvolvescreativethinking.Itcanthenbetested–bycomparingitspredictionswithdatafromobservationsormeasurements.
Candidates should understand that: A candidate who understands this can, for example:
3.1 • scientifichypotheses,explanationsandtheoriesarenotsimplysummariesoftheavailabledata.Theyarebasedondatabutaredistinctfromthem.
• inagivenaccountofscientificwork,identifystatementswhichreportdataandstatementsofexplanatoryideas(hypotheses,explanations,theories)
• recognisethatanexplanationmaybeincorrectevenifthedataagreewithit.
3.2 • anexplanationcannotsimplybededucedfromdata,buthastobethoughtupcreativelytoaccountforthedata.
• identifywherecreativethinkingisinvolvedinthedevelopmentofanexplanation.
3.3 • ascientificexplanationshouldaccountformost(ideallyall)ofthedataalreadyknown.Itmayexplainarangeofphenomenanotpreviouslythoughttobelinked.Itshouldalsoenablepredictionstobemadeaboutnewsituationsorexamples.
• recognisedataorobservationsthatareaccountedforby,orconflictwith,anexplanation
• givegoodreasonsforacceptingorrejectingaproposedscientificexplanation
• identifythebetteroftwogivenscientificexplanationsforaphenomenon,andgivereasonsforthechoice.
3.4 • scientificexplanationsaretestedbycomparingpredictionsbasedonthemwithdatafromobservationsorexperiments.
• drawvalidconclusionsabouttheimplicationsofgivendataforagivenscientificexplanation,inparticular:— understandthatagreementbetweena
predictionandanobservationincreasesconfidenceintheexplanationonwhichthepredictionisbasedbutdoesnotproveitiscorrect
— understandthatdisagreementbetweenapredictionandanobservationindicatesthatoneortheotheriswrong,anddecreasesourconfidenceintheexplanationonwhichthepredictionisbased.
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4 The scientific communityFindingsreportedbyanindividualscientistorgrouparecarefullycheckedbythescientificcommunitybeforebeingacceptedasscientificknowledge.
Candidates should understand that: A candidate who understands this can, for example:
4.1 • scientistsreporttheirclaimstootherscientiststhroughconferencesandjournals.Scientificclaimsareonlyacceptedoncetheyhavebeenevaluatedcriticallybyotherscientists.
• describeinbroadoutlinethe‘peerreview’process,inwhichnewscientificclaimsareevaluatedbyotherscientists
• recognisethatthereislessconfidenceinnewscientificclaimsthathavenotyetbeenevaluatedbythescientificcommunitythanthereisinwell-establishedones.
4.2 • scientistsareusuallyscepticalaboutclaimsthatcannotberepeatedbyanyoneelse,andaboutunexpectedfindingsuntiltheyhavebeenreplicated(bythemselves)orreproduced(bysomeoneelse).
• identifythefactthatafindinghasnotbeenreproducedbyanotherscientistasareasonforquestioningascientificclaim
• explainwhyscientistsseethisasimportant.
4.3 • ifexplanationscannotbededucedfromtheavailabledata,two(ormore)scientistsmaylegitimatelydrawdifferentconclusionsaboutthesamedata.Ascientist’spersonalbackground,experienceorinterestsmayinfluencehis/herjudgments.
• showawarenessthatthesamedatamightbeinterpreted,quitereasonably,inmorethanoneway
• suggestplausiblereasonswhyscientistsinagivensituationdisagree(d).
4.4 • anacceptedscientificexplanationisrarelyabandonedjustbecausesomenewdatadisagreewithitspredictions.Itusuallysurvivesuntilabetterexplanationisavailable.
• discussthelikelyconsequencesofnewdatathatdisagreewiththepredictionsofanacceptedexplanation
• suggest reasons why scientists should not give up an accepted explanation immediately if new data appear to conflict with it.
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5 RiskEveryactivityinvolvessomerisk.Assessingandcomparingtherisksofanactivity,andrelatingthesetothebenefitswegainfromit,areimportantindecisionmaking.
Candidates should understand that: A candidate who understands this can, for example:
5.1 • everythingwedocarriesacertainriskofaccidentorharm.Nothingisriskfree.Newtechnologiesandprocessesbasedonscientificadvancesoftenintroducenewrisks.
• explainwhyitisimpossibleforanythingtobecompletelysafe
• identifyexamplesofriskswhicharisefromanewscientificortechnologicaladvance
• suggestwaysofreducingagivenrisk.
5.2 • wecansometimesassessthesizeofariskbymeasuringitschanceofoccurringinalargesample,overagivenperiodoftime.
• interpretanddiscussinformationonthesizeofrisks,presentedindifferentways.
5.3 • tomakeadecisionaboutaparticularrisk,weneedtotakeaccountbothofthechanceofithappeningandtheconsequencesifitdid.
• discussagivenrisk,takingaccountofboththechanceofitoccurringandtheconsequencesifitdid.
5.4 • tomakeadecisionaboutacourseofaction,weneedtotakeaccountofbothitsrisksandbenefits,tothedifferentindividualsorgroupsinvolved.
• identifyrisksandbenefitsinagivensituation,tothedifferentindividualsandgroupsinvolved
• discussacourseofaction,withreferencetoitsrisksandbenefits,takingaccountofwhobenefitsandwhotakestherisks
• suggestbenefitsofactivitiesthatareknowntohaverisk.
5.5 • peoplearegenerallymorewillingtoaccepttheriskassociatedwithsomethingtheychoosetodothansomethingthatisimposed,andtoacceptrisksthathaveshort-livedeffectsratherthanlong-lastingones.
• offerreasonsforpeople’swillingness(orreluctance)toaccepttheriskofagivenactivity.
5.6 • people’s perception of the size of a particular risk may be different from the statistically estimated risk. People tend to over-estimate the risk of unfamiliar things (like flying as compared with cycling), and of things whose effect is invisible or long-term (like ionising radiation).
• distinguish between perceived and calculated risk, when discussing personal choices
• suggest reasons for given examples of differences between perceived and measured risk.
5.7 • governmentsandpublicbodiesmayhavetoassesswhatlevelofriskisacceptableinaparticularsituation.Thisdecisionmaybecontroversial,especiallyifthosemostatriskarenotthosewhobenefit.
• discussthepublicregulationofrisk,and explain why it may in some situations be controversial.
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6 Making decisions about science and technologyTomakesounddecisionsabouttheapplicationsofscientificknowledge,wehavetoweighupthebenefitsandcostsofnewprocessesanddevices.Sometimesthesedecisionsalsoraiseethicalissues.Societyhasdevelopedwaysofmanagingtheseissues,thoughnewdevelopmentscanposenewchallengestothese.
Candidates should understand that: A candidate who understands this can, for example:
6.1 • science-basedtechnologyprovidespeoplewithmanythingsthattheyvalue,andwhichenhancethequalityoflife.Someapplicationsofsciencecan,however,haveunintendedandundesirableimpactsonthequalityoflifeortheenvironment.Benefitsneedtobeweighedagainstcosts.
• inaparticularcontext,identifythegroupsaffectedandthemainbenefitsandcostsofacourseofactionforeachgroup
• suggest reasons why different decisions on the same issue might be appropriate in view of differences in social and economic context.
6.2 • scientistsmayidentifyunintendedimpactsofhumanactivity(includingpopulationgrowth)ontheenvironment.Theycansometimeshelpustodevisewaysofmitigatingthisimpactandofusingnaturalresourcesinamoresustainableway.
• identify,andsuggest,examplesofunintendedimpactsofhumanactivityontheenvironment
• explaintheideaofsustainability,andapplyittospecificsituations
• usedata(forexample,fromaLifeCycleAssessment)tocomparethesustainabilityofalternativeproductsorprocesses.
6.3 • inmanyareasofscientificwork,thedevelopmentandapplicationofscientificknowledgearesubjecttoofficialregulations.
• incontextswherethisisappropriate,showawarenessof,and discuss,theofficialregulationofscientificresearchandtheapplicationofscientificknowledge.
6.4 • somequestions,suchasthoseinvolvingvalues,cannotbeansweredbyscience.
• distinguishquestionswhichcouldinprinciplebeansweredusingascientificapproach,fromthosewhichcouldnot.
6.5 • someformsofscientificresearch,andsomeapplicationsofscientificknowledge,haveethicalimplications.Peoplemaydisagreeaboutwhatshouldbedone(orpermitted).
• whereanethicalissueisinvolved: sayclearlywhatthisissueis summarisedifferentviewsthatmaybe
held.
6.6 • indiscussionsofethicalissues,onecommonargumentisthattherightdecisionisonewhichleadstothebestoutcomeforthegreatestnumberofpeopleinvolved.Anotheristhatcertainactionsareconsideredrightorwrongwhatevertheconsequences.
• inagivencontext,identify,and develop,argumentsbasedontheideasthat: therightdecisionistheonewhichleads
tothebestoutcomeforthegreatestnumberofpeopleinvolved
certainactionsareconsideredrightorwrongwhatevertheconsequences.
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UnitA162istheunitwithinGCSEAdditionalScienceAwherethebiologycontentisassessed.ItassessesthecontentofModules B4, B5andB6togetherwiththeIdeasaboutScience.
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3.4 Summary of Unit A162: Biology A Modules B4, B5, B6
Biologicalprocessesthattakeplaceincellsinvolvechemicalreactionscatalysedbyenzymes.Photosynthesisandrespirationareexamplesoftheseprocesses,andthesereactionstakeplaceinspecialisedstructureswithincells.TheconditionsforoptimumenzymeactionrequiretemperatureandpHtobecontrolled.Anaerobicrespirationofmicroorganismsandyeastprovideshumanswithusefulproducts,includingbiogas,breadandalcohol.
Thefirsttopicconsiderssomeofthemostfundamentalchemicalreactionsthatoccurwithincellsandhighlightsthecrucialrolethatenzymesplayintheseprocesses.Thehighlyspecificnatureofenzymesisexplored,alongwithsensitivityofenzymestotheirenvironment.Thelockandkeymodelprovidesanaccessibleexampleofhowmodelsandanalogycanenhanceunderstandingofscientificprocesses.
Thesecondtopicfocusesinmoredetailonphotosynthesisandtheprocessesplantsutilisetotakeinandtransportwaterandnutrients,necessarytoproducethecomplexmoleculesrequiredforplantgrowth.
Theprocessesofplantgrowtharealsofundamentaltoprovidingtheglucoseandcomplexsugarsthatmanyanimalandmicrobiallifeformsdependuponforrespiration.Respirationisexploredinmoredetailinthethirdtopic.
TopicsB4.1 Howdochemicalreactionstakeplaceinlivingthings?ReactionsincellsRoleofenzymesB4.2 Howdoplantsmakefood?PhotosynthesisCellstructuresforphotosynthesisLimitingfactorsB4.3 Howdolivingorganismsobtainenergy?AerobicrespirationAnaerobicrespirationCellstructuresforrespiration
Thismoduleoffersopportunitiestodevelopmathematicsskills.Forexample:
• carryoutcalculationsusingexperimentaldata,includingfindingthemeanandtherange
• carryoutcalculationsusingfractionsandpercentages
• plot,drawandinterpretgraphsandchartsfromcandidates’ownandsecondarydata
• useideasaboutcorrelation.
Overview
3.4.1 Module B4: The processes of life
Opportunities for mathematics
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Opportunities for practical work
Thismoduleoffersopportunitiesforpracticalworkinteachingandlearning.Forexample:
• investigatehowseedbeetlesareabletosensetheirsurroundings
• investigatetheeffectsofanenzymeonbiologicalprocesses
• investigatethefactorsaffectingphotosynthesis
• usemicroscopestolookcarefullyatthestructureofleaves
• investigateratesofdiffusionindifferentmedia
• investigatetheeffectofsoluteconcentrationonpotatocellwaterbalance
• usesoilteststocomparesoilsandcomposts
• usefieldworktoinvestigatefactorsaffectingthespeciesofplantsindifferentenvironmentalconditions
• investigatetheenergycontentofdifferentfoods
• usedataloggingtotracktemperaturechangesduringrespirationinpeas
• investigateanaerobicrespirationinyeast.
ThismoduleoffersopportunitiestoillustratetheuseofICTinscience.Forexample:
• molecularmodellingtodevelopexplanationsofenzymeaction.
UseofICTinteachingandlearningcaninclude:
• animationstoexplainenzymeactionandtheeffectoftemperatureonenzymeactivity
• animationsofdiffusion,osmosisandactivetransport.
Opportunities for ICT
Opportunities for teaching the Ideas about Science
ExamplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopmentinthismoduleinclude:
laS1.1–1.6
laS2.1,2.2
Data: their importance and limitations
Cause-effect explanations
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Module B4: The processes of lifeB4.1 How do chemical reactions take place in living things?1. understandthatthebasicprocessesoflifecarriedoutbyalllivingthingsdependonchemical
reactionswithincellsthatrequireenergyreleasedbyrespiration2. understandtheroleofphotosynthesisinmakingfoodmoleculesandenergyavailableto
livingorganismsthroughfoodchains3. describephotosynthesisasaseriesofchemicalreactionsthatuseenergyfromsunlightto
buildlargefoodmoleculesinplantcellsandsomemicroorganisms(e.g.phytoplankton)4. describerespirationasaseriesofchemicalreactionsthatreleaseenergybybreakingdown
largefoodmoleculesinalllivingcells5. recallthatenzymesareproteinsthatspeedupchemicalreactions6. recallthatcellsmakeenzymesaccordingtotheinstructionscarriedingenes7. understandthatmoleculeshavetobethecorrectshapetofitintotheactivesiteofthe
enzyme(thelockandkeymodel)8. understandthatenzymesneedaspecificconstanttemperaturetoworkattheiroptimum,
andthattheypermanentlystopworking(denature)ifthetemperatureistoohigh9. explain that enzyme activity at different temperatures is a balance between: a. increased rates of reaction as temperature increases b. changes to the active site at higher temperatures, including denaturing Candidates are not expected to explain why rates of reaction increase with
temperature10. recallthatanenzymeworksatitsoptimumataspecificpH11. explain the effect of pH on enzyme activity in terms of changes to the shape of the
active site.
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Module B4: The processes of lifeB4.2 How do plants make food?1. recallthenamesofthereactantsandproductsofphotosynthesis,andusetheword
equation: lightenergy carbondioxide+water→glucose+oxygen2. recall the formulae of the reactants and products of photosynthesis, and use the
symbol equation: light energy 6CO2 + 6H2O → C6H12O6 + 6O2 3. recallthemainstagesofphotosynthesis: a. lightenergyabsorbedbythegreenchemicalchlorophyll b. energyusedtobringaboutthereactionbetweencarbondioxideandwaterto
produceglucose(asugar) c. oxygenproducedasawasteproduct4. recallthatglucosemaybe: a. convertedintochemicalsneededforgrowthofplantcells,forexamplecellulose,
proteinandchlorophyll b. convertedintostarchforstorage c. usedinrespirationtoreleaseenergy5. recallthestructureofatypicalplantcell,limitedtochloroplasts,cellmembrane,nucleus,
cytoplasm,mitochondria,vacuoleandcellwall6. understandthefunctionsofthestructuresinatypicalplantcellthathavearolein
photosynthesis,including: a. chloroplastscontainchlorophyllandtheenzymesforthereactionsinphotosynthesis b. cellmembraneallowsgasesandwatertopassinandoutofthecellfreelywhile
presentingabarriertootherchemicals c. nucleuscontainsDNAwhichcarriesthegeneticcodeformakingenzymesandother
proteinsusedinthechemicalreactionsofphotosynthesis d. cytoplasmwheretheenzymesandotherproteinsaremade7. recallthatmineralstakenupbyplantrootsareusedtomakesomechemicalsneededby
cells,includingnitrogenfromnitratestomakeproteins8. understandthatdiffusionisthepassiveoverallmovementofmoleculesfromaregionoftheir
higherconcentrationtoaregionoftheirlowerconcentration9. recallthatthemovementofoxygenandcarbondioxideinandoutofleavesduring
photosynthesisoccursbydiffusion10. understandthatosmosis(aspecificcaseofdiffusion)istheoverallmovementofwaterfrom
adilutetoamoreconcentratedsolutionthroughapartiallypermeablemembrane11. recallthatthemovementofwaterintoplantrootsoccursbyosmosis12. understand that active transport is the overall movement of chemicals across a cell
membrane requiring energy from respiration13. recall that active transport is used in the absorption of nitrates by plant roots
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B4.2 How do plants make food?
14. understandthattherateofphotosynthesismaybelimitedby: a. temperature b. carbondioxide c. lightintensity15. interpretdataonfactorslimitingtherateofphotosynthesis16. describeandexplaintechniquesusedinfieldworktoinvestigatetheeffectoflightonplants,
including: a. usingalightmeter b. usingaquadrat c. usinganidentificationkey17. understandhowtotakeatransect.
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Module B4: The processes of lifeB4.3 How do living organisms obtain energy?1. understandthatalllivingorganismsrequireenergyreleasedbyrespirationforsome
chemicalreactionsincells,includingchemicalreactionsinvolvedin: a. movement b. synthesisoflargemolecules c. active transport2. understandthatsynthesisoflargemoleculesincludes: a. synthesisofpolymersrequiredbyplantcellssuchasstarchandcellulosefrom
glucoseinplantcells b. synthesisofaminoacidsfromglucoseandnitrates,andthenproteinsfromamino
acidsinplant,animalandmicrobialcells3. recallthataerobicrespirationtakesplaceinanimalandplantcellsandsome
microorganisms,andrequiresoxygen4. recallthenamesofthereactantsandproductsofaerobicrespirationandusetheword
equation: glucose+oxygen→carbondioxide+water(+energyreleased)5. recall the formulae of the reactants and products of aerobic respiration and use the
symbol equation: C6H12O6 + 6O2 → 6CO2 + 6H2O6. recallthatanaerobicrespirationtakesplaceinanimal,plantandsomemicrobialcellsin
conditionsoflowoxygenorabsenceofoxygen,toinclude: a. plantrootsinwaterloggedsoil b. bacteriainpuncturewounds c. humancellsduringvigorousexercise7. recallthenamesofthereactantsandproductsofanaerobicrespirationinanimalcellsand
somebacteria,andusethewordequation: glucose→lacticacid(+energyreleased)8. recallthenamesofthereactantsandproductsofanaerobicrespirationinplantcellsand
somemicroorganismsincludingyeast,andusethewordequation: glucose→ethanol+carbondioxide(+energyreleased)9. understandthataerobicrespirationreleasesmoreenergyperglucosemoleculethan
anaerobicrespiration10. recallthestructureoftypicalanimalandmicrobialcells(bacteriaandyeast)limitedto: a. nucleus b. cytoplasm c. cellmembrane d. mitochondria(foranimalandyeastcells) e. cellwall(foryeastandbacterialcells) f. circularDNAmolecule(forbacterialcells)
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B4.3 How do living organisms obtain energy?
11. understandthefunctionsofthestructuresinanimal,plant,bacteriaandyeastcellsthathavearoleinrespiration,including:
a. mitochondriacontainenzymesforthereactionsinaerobicrespiration(inanimals,plantsandyeast)
b. cellmembraneallowsgasesandwatertopassinandoutofthecellfreelywhilepresentingabarriertootherchemicals
c. nucleusorcircularDNAinbacteriacontainsDNAwhichcarriesthegeneticcodeformakingenzymesusedinthechemicalreactionsofrespiration
d. cytoplasmwhereenzymesaremadeandwhichcontainstheenzymesusedinanaerobicrespiration
12. describeexamplesoftheapplicationsoftheanaerobicrespirationofmicroorganisms,includingtheproductionofbiogasandfermentationinbreadmakingandalcoholproduction.
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Genetictechnologiesareatthecuttingedgeofcontemporaryscience.Researchintoproteomics,stemcelltechnologyandcellulargrowthcontrolisattheforefrontofmodernmedicalscience.Knowledgeandunderstandingoftheseareaspromisepowerfulapplicationstobenefitbothpresentandfuturegenerations.
Thefirsttopicexplainsplantandanimaldevelopment,comparingandcontrastingthedevelopmentofunspecialisedcells.Theabilityofplantmeristemstoregeneratewholeplantsisconsidered,includingtheeffectofplanthormonesontheirdevelopment.
ThesecondtopiclooksathowthestructureofDNAallowscellstobeaccuratelycopied.Keystagesinthecellcycleareidentified,andcelldivisionbymitosisandmeiosiscompared.
Thefinaltopicdescribestheprocessofproteinsynthesis,followingtheone-gene-one-proteinhypothesis.
Thismoduleoffersopportunitiestodevelopmathematicsskills.Forexample:
• developasenseofscaleinthecontextofDNA,cellsandplants
• carryoutcalculationsusingfractionsandpercentages
• plot,drawandinterpretgraphsandchartsfromcandidates’ownandsecondarydata.
Thismoduleoffersopportunitiesforpracticalworkinteachingandlearning.Forexample:
• usemicroscopestolookatavarietyofplantandanimalcells
• dissectanddrawabroadbean
• takeplantcuttingsandinvestigatetheeffectsofusinghormonerootingpowder
• investigatetheeffectsofphototropism
• viewgerminatingpollen
• extractDNAfromplants.
Overview
3.4.2 Module B5: Growth and development
TopicsB5.1 Howdoorganismsdevelop?Embryodevelopment;cellspecialisationinplantsandanimals;plantgrowthresponsesB5.2 Howdoesanorganismproducenewcells?Mainprocessesofthecellcycle;comparisonsofmitosisandmeiosisB5.3 Howdogenescontrolgrowthanddevelopmentwithinthecell?Structureofgeneticcodeandmechanismforproteinsynthesis
Opportunities for mathematics
Opportunities for practical work
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ExamplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopmentinthismoduleinclude:
laS3.1–3.4
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ThismoduleoffersopportunitiestoillustratetheuseofICTinscience.Forexample:
• imagingcellsandobservingtheirgrowthanddevelopment.
UseofICTinteachingandlearningcaninclude:
• animationstoillustrateDNAstructure,replication,andproteinsynthesis
• animationstoillustratecelldivision
• videoclipstoshowstagesinhumandevelopment.
Opportunities for ICT
Opportunities for teaching the Ideas about Science
Developing scientific explanations
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Module B5: Growth and developmentB5.1 How do organisms develop?1. recallthatcellsinmulticellularorganismscanbespecialisedtodoparticularjobs2. recallthatgroupsofspecialisedcellsarecalledtissues,andgroupsoftissuesformorgans3. recallthatafertilisedeggcell(zygote)dividesbymitosistoformanembryo4. recallthatinahumanembryoupto(andincluding)theeightcellstage,allthecellsare
identical(embryonicstemcells)andcouldproduceanytypeofcellrequiredbytheorganism5. understandthataftertheeightcellstage,mostoftheembryocellsbecomespecialisedand
formdifferenttypesoftissue6. understandthatsomecells(adultstemcells)remainunspecialisedandcanbecome
specialised,atalaterstage,tobecomemany,butnotall,typesofcellrequiredbytheorganism
7. understandthatinplants,onlycellswithinspecialregionscalledmeristemsaremitoticallyactive
8. understandthatthenewcellsproducedfromplantmeristemsareunspecialisedandcandevelopintoanykindofplantcell
9. understandthatunspecialisedplantcellscanbecomespecialisedtoformdifferenttypesoftissue(includingxylemandphloem)withinorgans(includingflowers,leaves,stemsandroots)
10. understandthatthepresenceofmeristems(assourcesofunspecialisedcells)allowstheproductionofclonesofaplantfromcuttings,andthatthismaybedonetoreproduceaplantwithdesirablefeatures
11. understandthatacutstemfromaplantcandeveloprootsandthengrowintoacompleteplantwhichisacloneoftheparent,andthatrootingcanbepromotedbythepresenceofplanthormones(auxins)
12. understandthatthegrowthanddevelopmentofplantsisalsoaffectedbytheenvironment,e.g.phototropism
13. understandhowphototropismincreasestheplant’schanceofsurvival14. explain phototropism in terms of the effect of light on the distribution of auxin in a
shoot tip.
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Module B5: Growth and developmentB5.2 How does an organism produce new cells?1. recallthatcelldivisionbymitosisproducestwonewcellsthataregeneticallyidenticalto
eachotherandtotheparentcell2. describethemainprocessesofthecellcycle: a. cellgrowthduringwhich: • numbersoforganellesincrease • thechromosomesarecopiedwhenthetwostrandsofeachDNAmolecule
separateandnewstrandsformalongsidethem b. mitosisduringwhich: • copiesofthechromosomesseparate • thenucleusdivides
Candidates are not expected to recall intermediate stages of mitosis3. recallthatmeiosisisatypeofcelldivisionthatproducesgametes4. understandwhy,inmeiosis,itisimportantthatthecellsproducedonlycontainhalfthe
chromosomenumberoftheparentcell Candidates are not expected to recall intermediate stages of meiosis5. understandthatazygotecontainsasetofchromosomesfromeachparent.
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Module B5: Growth and developmentB5.3 How do genes control growth and development within the cell?1. recallthatDNAhasadoublehelixstructure2. recallthatbothstrandsoftheDNAmoleculearemadeupoffourdifferentbaseswhich
alwayspairupinthesameway:AwithT,andCwithG3. understandthattheorderofbasesinageneisthegeneticcodefortheproductionofa
protein4. explain how the order of bases in a gene is the code for building up amino acids in the
correct order to make a particular protein
Candidates are not expected to recall details of nucleotide structure, transcription or translation
5. recallthatthegeneticcodeisinthecellnucleusofanimalandplantcellsbutproteinsareproducedinthecellcytoplasm
6. understandthatgenesdonotleavethenucleusbutacopyofthegene(messenger RNA)isproducedtocarrythegeneticcodetothecytoplasm
7. understandthatalthoughallbodycellsinanorganismcontainthesamegenes,manygenesinaparticularcellarenotactive(switchedoff)becausethecellonlyproducesthespecificproteinsitneeds
8. understandthatinspecialisedcellsonlythegenesneededforthecellcanbeswitchedon,butinembryonicstemcellsanygenecanbeswitchedonduringdevelopmenttoproduceanytypeofspecialisedcell
9. understandthatadultstemcellsandembryonicstemcellshavethepotentialtoproducecellsneededtoreplacedamagedtissues
10. understandthatethicaldecisionsneedtobetakenwhenusingembryonicstemcellsandthatthisworkissubjecttoGovernmentregulation
11. understand that, in carefully controlled conditions of mammalian cloning, it is possible to reactivate (switch on) inactive genes in the nucleus of a body cell to form cells of all tissue types.
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Howthehumanbrainfunctionsremainslargelyunknown.Neuroscienceisanareaatthefrontierofmedicalresearch,andhashugepotentialimpactforanageingpopulation.
Thismodulebeginsbylookingathow,inordertosurvive,simpleorganismsrespondtochangesintheirenvironment.Thenervoussystemofmulticellularanimalsisalsoconsidered.
Thesecondtopicconsidershowinformationistransmittedfromreceptorcellstoeffectorcells,includingasimpledescriptionofchemicaltransmissionacrosssynapses.Theeffectsofdrugsonsynapsesinthebrainareexplored(forexample,Ecstasy).
Simple,conditionedandmodifiedreflexesareintroducedinthethirdtopic,withreferencetosurvivalandadaptation.
Thefourthtopictakesacloserlookatthebrain,andhowsomeneuronpathwaysbecome‘preferred’whileotherpotentialpathwaysremainavailabletoallowforadaptationtonewsituations.Thistopicillustratesspecialisedareasofthebrain,identifiesmethodsscientistshaveusedtomapthecerebralcortexandintroducesabasicunderstandingofmemory.
Thismoduleoffersopportunitiestodevelopmathematicsskills.Forexample:
• carryoutcalculationsusingexperimentaldata,includingfindingthemeanandtherange
• plot,drawandinterpretgraphsandchartsfromcandidates’ownandsecondarydata.
Overview
3.4.3 Module B6: Brain and mind
TopicsB6.1 Howdoanimalsrespondtochangesintheirenvironment?Co-ordinationofresponsestostimuliviathecentralnervoussystemB6.2 Howisinformationpassedthroughthenervoussystem?Structureofneurons;transmissionofelectricalimpulses,includingsynapses;effectsofEcstasyonsynapseactionB6.3 Whatcanwelearnthroughconditioning?Simplereflexactionsforsurvival;mechanismofareflexarc;conditionedreflexesB6.4 Howdohumansdevelopmorecomplexbehaviour?Formationofneuronpathwaysandlearningthroughrepetition;mappingbrainfunction;modelsforunderstandingmemory
Opportunities for mathematics
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Thismoduleoffersopportunitiesforpracticalworkinteachingandlearning.Forexample:
• investigatereflexbehaviourofwoodlice
• lookatmicroscopeslidesofneurons
• researchreflexbehaviourinnewbornbabiesandinotheranimals
• investigatereceptorcellsonthetongue
• measurethespeedatwhichanerveimpulsetravels
• investigatefactorsthataffectreactiontimes
• measurethetouchsensitivityofdifferentareasofthebody
• makeapresentationaboutPavlovandhisworkonconditionedreflexes
• investigatehowpracticeofaskillimprovesperformance
• investigatepupils’ownlearning
• investigatewhetherwoodlicehaveamemory.
ThismoduleoffersopportunitiestoillustratetheuseofICTinscience.Forexample:
• observeanddigitallyrecordhumanandanimalbehaviour
• log,recordanddisplayphysiologicaldata.
UseofICTinteachingandlearningcaninclude:
• videoclipstoillustratepatternsinthebehaviouroflivingthings
• animationstoexplainsynapsefunctionandtheeffectsofdrugsonsynapses
• interactiveanimationsonbrainfunction
• usingtheinternettoresearchbehaviourandmemory.
Opportunities for practical work
Opportunities for ICT
Opportunities for teaching the Ideas about Science
ExamplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopmentinthismoduleinclude:
laS6.5,6.6
Making decisions about science and technology
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Module B6: Brain and mindB6.1 How do animals respond to changes in their environment?1. recallthatastimulusisachangeintheenvironmentofanorganism2. understandthatsimplereflexesproducerapidinvoluntaryresponsestostimuli3. understandthatthesimplestanimalsrelyonreflexactionsforthemajorityoftheirbehaviour4. understandthatthesereflexactionshelptoensurethatthesimplestanimalsrespondto
astimulusinawaythatismostlikelytoresultintheirsurvival,toincludefindingfoodandshelteringfrompredators
5. recallexamplesofsimplereflexesinhumans,toincludenewbornreflexes(e.g.stepping,grasping,sucking),pupilreflex,kneejerkanddroppingahotobject
6. understandthatnervousco-ordination,includingsimplereflexes,requires: a. receptorstodetectstimuli b. processingcentrestoreceiveinformationandcoordinateresponses c. effectorstoproducetheresponse7. understandthatreceptorsandeffectorscanformpartofcomplexorgans,forexample: a. lightreceptorcellsintheretinaoftheeye b. hormonesecretingcellsinagland c. musclecellsinamuscle8. understandthatnervoussystemsuseelectricalimpulsesforfast,short-livedresponses
includingsimplereflexes9. recallthathormonesarechemicalsthatareproducedinglands,travelinthebloodandbring
aboutslower,longer-lastingresponses,e.g.insulinandoestrogen10. recallthatthedevelopmentofnervousandhormonalcommunicationsystemsdependedon
theevolutionofmulticellularorganisms.
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Module B6: Brain and mindB6.2 How is information passed through the nervous system?1. recallthatnervoussystemsaremadeupofneurons(nervecells)linkingreceptorcells(e.g.
ineyes,earsandskin)toeffectorcells(inmuscles/glands)2. recallthatneuronstransmitelectricalimpulseswhenstimulated3. recallthatanaxonisalongextensionofthecytoplasminaneuronandissurroundedbya
cellmembrane4. understandthatsomeaxonsaresurroundedbyafattysheath,whichinsulatestheneuron
fromneighbouringcellsandincreasesthespeedoftransmissionofanerveimpulse5. recallthatinhumansandothervertebratesthecentralnervoussystem(CNS)ismadeupof
thespinalcordandbrain6. recallthatinthemammaliannervoussystemtheCNS(brainandspinalcord)isconnected
tothebodyviatheperipheralnervoussystem(PNS)(sensoryandmotorneurons)7. understandthattheCNScoordinatesananimal’sresponsesvia: a. sensoryneuronscarryingimpulsesfromreceptorstotheCNS b. motorneuronscarryingimpulsesfromtheCNStoeffectors8. understandthatwithintheCNS,impulsesarepassedfromsensoryneuronstomotor
neuronsthroughrelayneurons9. describethenervouspathwayofaspinalreflexarctoincludereceptor,sensoryneuron,
relayneuron,spinalcord,motorneuronandeffector10. understand that this arrangement of neurons into a fixed pathway allows reflex
responses to be automatic and so very rapid, since no processing of information is required
11. recallthattherearegapsbetweenadjacentneuronscalledsynapsesandthatimpulsesaretransmittedacrossthem
12. understand that at a synapse an impulse triggers the release of chemicals (transmitter substances) from the first neuron into the synapse, which diffuse across and bind to receptor molecules on the membrane of the next neuron
13. understand that only specific chemicals bind to the receptor molecules, initiating a nerve impulse in the next neuron
14. recallthatsometoxinsanddrugs,includingEcstasy,betablockersandProzac,affectthetransmissionofimpulsesacrosssynapses
15. understand that Ecstasy (MDMA) blocks the sites in the brain’s synapses where the transmitter substance, serotonin, is removed
16. understand that the effects of Ecstasy on the nervous system are due to the subsequent increase in serotonin concentration
17. recallthatthecerebralcortexisthepartofourbrainmostconcernedwithintelligence,memory,languageandconsciousness
18. understandthatscientistscanmaptheregionsofthebraintoparticularfunctions(includingstudiesofpatientswithbraindamage,studiesinwhichdifferentpartsofthebrainarestimulatedelectrically,andbrainscanssuchasMRI,showingbrainstructureandactivity).
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Module B6: Brain and mindB6.3 Can reflex responses be learned?1. understandthatareflexresponsetoanewstimuluscanbelearnedbyintroducingthe
secondary(new)stimulusinassociationwiththeprimarystimulus,andthatthisiscalledconditioning
2. describeandexplaintwoexamplesofconditioning,includingPavlov’sdogs3. understand that in a conditioned reflex the final response (e.g. salivation) has no
direct connection to the secondary stimulus (e.g. ringing of a bell)4. understand that conditioned reflexes are a form of simple learning that can increase
an animal’s chance of survival5. recall that in some circumstances the brain can modify a reflex response via a neuron
to the motor neuron of the reflex arc, for example keeping hold of a hot object.
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Module B6: Brain and mindB6.4 How do humans develop more complex behaviour?1. understandthattheevolutionofalargerbraingaveearlyhumansabetterchanceofsurvival2. recallthatmammalshaveacomplexbrainofbillionsofneuronsthatallowslearningby
experience,includingsocialbehaviour3. understandthatduringdevelopmenttheinteractionbetweenmammalsandtheir
environmentresultsinneuronpathwaysforminginthebrain4. understandthatlearningistheresultofexperiencewhere: a. certainpathwaysinthebrainbecomemorelikelytotransmitimpulsesthanothers b. newneuronpathwaysformandotherneuronpathwaysarelost5. understandthatthisiswhysomeskillsmaybelearntthroughrepetition6. understand that the variety of potential pathways in the brain makes it possible for the
animal to adapt to new situations7. understand the implications of evidence suggesting that children may only acquire
some skills at a particular age, to include language development in feral children8. describememoryasthestorageandretrievalofinformation9. recallthatmemorycanbedividedintoshort-termmemoryandlong-termmemory10. understandthathumansaremorelikelytorememberinformationif: a. theycanseeapatterninit(orimposeapatternonit) b. thereisrepetitionoftheinformation,especiallyoveranextendedperiodoftime c. thereisastrongstimulusassociatedwithit,includingcolour,light,smell,orsound11. understandhowmodelscanbeusedtodescribememory(includingthemulti-storemodel)to
includeshort-termmemory,long-termmemory,repetition,storage,retrievalandforgetting12. understandthatmodelsarelimitedinexplaininghowmemoryworks.
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UnitA172istheunitwithinGCSEAdditionalScienceAwherethechemistrycontentisassessed.ItassessesthecontentofModules C4, C5 and C6togetherwithIdeasaboutScience.
3.5 Summary of Unit A172: Chemistry A Modules C4, C5, C6
Thismodulefeaturesacentralthemeofmodernchemistry.Itshowshowtheoriesofatomicstructurecanbeusedtoexplainthepropertiesofelementsandtheircompounds.Themodulealsoincludesexamplestoshowhowspectraandspectroscopyhavecontributedtothedevelopmentofchemicalknowledgeandtechniques.Thismoduleshowshowatomicstructurecanbeusedtohelpexplainthebehaviourofelements.
ThefirsttopiclooksatthePeriodicTable,thehistoryofitsdevelopment,andpatternsthatexistwithinit,focusingonGroup1andGroup7.Thistopicalsointroducestheuseofsymbolsandequationsasameansofdescribingachemicalreaction.Anexplanationofthepatternsisthendevelopedinthenexttopicbylinkingatomicstructurewithchemicalproperties.
Thethird,andfinal,topictakesthisfurtherbyintroducingionsandshowinghowionictheorycanaccountforpropertiesofcompoundsofGroup1withGroup7elements.
Overview
3.5.1 Module C4: Chemical patterns
TopicsC4.1 Whatarethepatternsinthepropertiesofelements?
ThehistoryofthedevelopmentofthePeriodicTableClassifyingelementsbytheirpositioninthePeriodicTablePatternsinGroup1andpatternsinGroup7UsingsymbolsandequationstorepresentchemicalreactionsC4.2 Howdochemistsexplainthepatternsinthepropertiesofelements?
FlametestsandspectraandtheiruseforidentifyingelementsandstudyingatomicstructureClassifyingelementsbytheiratomicstructureLinkingatomicstructuretochemicalpropertiesC4.3 HowdochemistsexplainthepropertiesofcompoundsofGroup1andGroup7elements?Ions,andlinkingionformationtoatomicstructurePropertiesofioniccompoundsofalkalimetalsandhalogens
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Thismoduleoffersopportunitiestodevelopmathematicsskills.Forexample:
• developasenseofscaleinthecontextofatomicstructure
• useideasofratiosinthecontextoftheformulaeofioniccompounds
• plot,drawandinterpretgraphsandchartsfromsecondarydata
• extractinformationfromthePeriodicTable
• extractinformationfromchartsandgraphsincludingpatternsinthepropertiesofelements
• balancechemicalequations.
Opportunities for mathematics
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Thismoduleoffersopportunitiesforpracticalworkinteachingandlearning.Forexample:
• reactionsofthealkalimetals
• reactionsofthehalogens
• experimentstotestthepropertiesofioniccompounds.
ThismoduleoffersopportunitiestoillustratetheuseofICTinscience.Forexample:
• storinglargesetsofdata
• selectingandpresentingdatainavarietyofformstoexplorepatternsandtrends.
UseofICTinteachingandlearningcaninclude:
• usinganinteractivePeriodicTabletoexploresimilaritiesanddifferencesbetweenelements
• usingaspreadsheettodisplaypatternsinchemicaldata
• videoclipstotestpredictionsaboutthereactionsofelementssuchascaesiumandfluorine
• usingtheinternettoresearchtheusesofalkalimetalsorhalogensandtheircompounds.
Opportunities for practical work
Opportunities for ICT
Opportunities for teaching the Ideas about Science
ExamplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopmentinthismoduleinclude:
laS3.1–3.4
laS4.1–4.4
Developing scientific explanations
The scientific community
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Module C4: Chemical patternsC4.1 What are the patterns in the properties of elements?1. understandthatatomsofeachelementhavedifferentprotonnumbers2. understandthatarrangingtheelementsinorderoftheirprotonnumbersgivesrepeating
patternsinthepropertiesofelements3. understandthatearlyattemptstofindconnectionsbetweenthechemicalpropertiesofthe
elementsandtheirrelativeatomicmassweredismissedbythescientificcommunity4. recallthesignificantstagesinthehistoryofthedevelopmentofthePeriodicTabletoinclude
theideasofDöbereiner,NewlandsandMendeleev5. understandhowMendeleevusedhisPeriodicTabletopredicttheexistenceofunknown
elements6. usethePeriodicTabletoobtainthenames,symbols,relativeatomicmassesandproton
numbersofelements7. understandthatagroupofelementsisaverticalcolumninthePeriodicTableandthatthe
elementsinagrouphavesimilarproperties8. recallthataperiodisarowofelementsinthePeriodicTable9. usethePeriodicTabletoclassifyanelementasametalornon-metal10. usepatternsinthePeriodicTabletointerpretdataandpredictpropertiesofelements Candidates will be given a copy of the Periodic Table (as in Appendix F) with the
examination paper11. recallandrecognisethechemicalsymbolsfortheGroup1metals(alsoknownasthealkali
metals)lithium,sodiumandpotassium12. recallthatthealkalimetalsareshinywhenfreshlycutbuttarnishrapidlyinmoistairdueto
reactionwithoxygen13. usequalitativeandquantitativedatatoidentifypatternsandmakepredictionsaboutthe
propertiesofGroup1metals(forexample,meltingpoint,boilingpoint,density,formulaeofcompoundsandrelativereactivity)
14. describethereactionsoflithium,sodiumandpotassiumwithcoldwater15. recallthatalkalimetalsreactwithwatertoformhydrogenandanalkalinesolutionofa
hydroxidewiththeformulaMOH16. recallthatalkalimetalsreactvigorouslywithchlorinetoformcolourless,crystallinesaltswith
theformulaMCl17. understandandgiveexamplestoshowthatthealkalimetalsbecomemorereactiveasthe
groupisdescended18. recallthemainhazardsymbolsandbeabletogivethesafetyprecautionsforhandling
hazardouschemicals(limitedtoexplosive,toxic,corrosive,oxidizing,andhighlyflammable) See Appendix H for guidance on recent changes to hazard labelling19. stateandexplaintheprecautionsnecessarywhenworkingwithGroup1metalsandalkalis20. recallandrecognisethechemicalsymbolsfortheatomsoftheGroup7elements(also
knownasthehalogens)chlorine,bromineandiodine21. recallthestatesofthesehalogensatroomtemperatureandpressure22. recallthecoloursofthesehalogensintheirnormalphysicalstateatroomtemperatureand
asgases23. recallthatthehalogensconsistofdiatomicmolecules
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C4.1 What are the patterns in the properties of elements?
24. usequalitativeandquantitativedatatoidentifypatternsandmakepredictionsaboutthepropertiesoftheGroup7elements(forexamplemeltingpoint,boilingpoint,formulaeofcompoundsandrelativereactivity)
25. understandthatthehalogensbecomelessreactiveasthegroupisdescendedandgiveexamplestoshowthis
26. understandhowatrendinreactivityforhalogenscanbeshownbytheirdisplacementreactionsandbytheirreactionswithalkalimetalsandwithiron
27. stateandexplainthesafetyprecautionsnecessarywhenworkingwiththehalogens28. recalltheformulaeof: a. hydrogen,waterandhalogen(limitedtochlorine,bromineandiodine)molecules b. thechlorides,bromides and iodides (halides)ofGroup1metals(limitedtolithium,
sodiumandpotassium)29. writewordequationsforreactionsofalkalimetalsandhalogensinthismoduleandforother
reactionswhengivenappropriateinformation30. interpretsymbolequations,includingthenumberofatomsofeachelement,thenumber
ofmoleculesofeachelementorcovalentcompoundandthenumberof‘formulas’ofioniccompounds,inreactantsandproducts
In this context, ‘formula’ is used in the case of ionic compounds as an equivalent to molecules in covalent compounds; the concept of the mole is not covered in the specification
31. balance unbalanced symbol equations32. write balanced equations, including the state symbols (s), (g), (l ) and (aq), for
reactions of alkali metals and halogens in this module and for other reactions when given appropriate information
33. recallthestatesymbols(s),(l ),(g)and(aq)andunderstandtheiruseinequations.
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Module C4: Chemical patternsC4.2 How do chemists explain the patterns in the properties of elements?1. describethestructureofanatomintermsofprotonsandneutronsinaverysmallcentral
nucleuswithelectronsarrangedinshellsaroundthenucleus2. recalltherelativemassesandchargesofprotons,neutronsandelectrons3. understandthatinanyatomthenumberofelectronsequalsthenumberofprotons4. understandthatalltheatomsofthesameelementhavethesamenumberofprotons5. understandthattheelementsinthePeriodicTablearearrangedinorderofprotonnumber6. recallthatsomeelementsemitdistinctiveflamecolourswhenheated(forexamplelithium,
sodiumandpotassium) Recall of specific flame colours emitted by these elements is not required7. understandthatthelightemittedfromaparticularelementgivesacharacteristicline
spectrum8. understandthatthestudyofspectrahashelpedchemiststodiscovernewelements9. understandthatthediscoveryofsomeelementsdependedonthedevelopmentofnew
practicaltechniques(forexamplespectroscopy)10. use the Periodic Table to work out the number of protons, electrons and neutrons in
an atom11. usesimpleconventions,suchas2.8.1anddotsincircles,torepresenttheelectron
arrangementsintheatomsofthefirst20elementsinthePeriodicTable,whenthenumberofelectronsorprotonsintheatomisgiven(or can be derived from the Periodic Table)
12. understandthatashell(orenergylevel)fillswithelectronsacrossaperiod13. understandthatelementsinthesamegrouphavethesamenumberofelectronsintheir
outershellandhowthisrelatestogroupnumber14. understand that the chemical properties of an element are determined by its electron
arrangement, illustrated by the electron configurations of the atoms of elements in Groups 1 and 7.
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Module C4: Chemical patternsC4.3 How do chemists explain the properties of compounds of Group 1 and Group 7
elements?1. understandthatmoltencompoundsofmetalswithnon-metalsconductelectricityandthat
thisisevidencethattheyaremadeupofchargedparticlescalledions2. understandthatanionisanatom(orgroupofatoms)thathasgainedorlostelectronsand
sohasanoverallcharge3. accountforthechargeontheionsofGroup1andGroup7elementsbycomparingthe
numberandarrangementoftheelectronsintheatomsandionsoftheseelements4. work out the formulae of ionic compounds given the charges on the ions5. work out the charge on one ion given the formula of a salt and the charge on the other
ion6. recallthatcompoundsofGroup1metalswithGroup7elementsareionic7. understandthatsolidioniccompoundsformcrystalsbecausetheionsarearrangedina
regularlattice8. describewhathappenstotheionswhenanioniccrystalmeltsordissolvesinwater9. explainthationiccompoundsconductelectricitywhenmoltenorwhendissolvedinwater
becausetheionsarechargedandtheyareabletomovearoundindependentlyintheliquid.
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Chemistryisfundamentaltoanunderstandingofthescaleandsignificanceofhumanimpactsonthenaturalenvironment.Knowledgeofnaturalprocessesmakesitpossibletoappreciatetheenvironmentalconsequencesofextractingandprocessingminerals.
Themoduleusesenvironmentalcontextstointroducetheoriesofstructureandbonding.Thefirsttopicexplainsthecharacteristicsofcovalentbonding,andintermolecularforcesinthecontextofthechemicalsfoundintheatmosphere.Thesecondtopicexplainsionicbondinginthecontextofreactionsinthehydrosphere,andincludesthedetectionandidentificationofions.
ThethirdtopiclooksatthepropertiesofgiantstructureswithstrongcovalentbondingfoundintheEarth’scrust,includingsilicondioxide.Thefinaltopiccoversthedistribution,structureandpropertiesofmetalsthroughastudyoftheirextractionfromores.Thisincludestheuseofrelativeatomicmassestogiveaquantitativeinterpretationofchemicalformulae.
Thismoduleoffersopportunitiestodevelopmathematicsskills.Forexample:
• developasenseofscaleinthecontextoftheEarthanditsatmosphere
• carryoutcalculationstofindthepercentageofanelementinacompoundandthemassofanelementthatcanbeobtainedfromitscompound
• plot,drawandinterpretgraphsandchartsfromcandidates’ownandsecondarydata
• extractinformationfromcharts,graphsandtablesincludingtheabundanceofelementsontheEarth
• calculaterelativeformulamasses
• balanceionicequations.
Overview
3.5.2 Module C5: Chemicals of the natural environment
TopicsC5.1 Whattypesofchemicalsmakeuptheatmosphere?ThestructureandpropertiesofchemicalsfoundintheatmosphereC5.2 Whatreactionshappeninthehydrosphere?Thestructureandpropertiesofchemicalsfoundinthehydrosphere,anddetectingandidentifyingionsC5.3 WhattypesofchemicalsmakeuptheEarth’slithosphere?RelatingthepropertiesofchemicalstotheirgiantstructureusingexamplesfoundintheEarth’slithosphereC5.4 Howcanweextractusefulmetalsfromminerals?RelatingthestructureandpropertiesofmetalstosuitablemethodsofextractionUsingionictheorytoexplainelectrolysisDiscussingissuesrelatingtometalextractionandrecycling
Opportunities for mathematics
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Thismoduleoffersopportunitiesforpracticalworkinteachingandlearning.Forexample:
• crystallisationexperiments
• usingprecipitationreactionstoidentifyionsinsalts
• extractingmetalswithcarbon
• extractingmetalsbyelectrolysis.
ThismoduleoffersopportunitiestoillustratetheuseofICTinscience.Forexample:
• modellingmoleculesandgiantstructurestoexplainproperties.
UseofICTinteachingandlearningcaninclude:
• animationstoshowthemovementofmoleculesinagasoverarangeoftemperatures
• modellingsoftwaretoshowtheshapesofmoleculesandillustrategiantstructures
• videoclipstoshowmetalsbeingextractedonalargescale
• animationstoillustratetheionictheoryofelectrolysis.
Opportunities for practical work
Opportunities for ICT
Opportunities for teaching the Ideas about Science
ExamplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopmentinthismoduleinclude:
laS3.1,3.2
laS5.1
laS6.1,6.2,6.5,6.6
Developing scientific explanations
Risk
Making decisions about science and technology
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Module C5: Chemicals of the natural environmentC5.1 What types of chemicals make up the atmosphere?1. recallthatdryairconsistsofgases,someofwhichareelements(forexample,oxygen,
nitrogenandargon)andsomeofwhicharecompounds(forexample,carbondioxide)2. recallthattherelativeproportionsofthemaingasesintheatmosphereareabout78%
nitrogen,21%oxygen,1%argonand0.04%carbondioxide3. recallthesymbolsfortheatomsandmoleculesofthesegasesintheair4. recallthatmostnon-metalelementsandmostcompoundsbetweennon-metalelementsare
molecular5. understandthatmolecularelementsandcompoundswithsmallmoleculeshavelowmelting
andboilingpoints6. interpretquantitativedata(forexample,meltingandboilingpoints)andqualitativedataabout
thepropertiesofmolecularelementsandcompounds7. understandthatmolecularelementsandcompounds,suchasthoseintheair,havelow
meltingandboilingpoints,andaregasesatroomtemperature,becausetheyconsistofsmallmoleculeswithweakforcesofattractionbetweenthemolecules
8. understandthatpuremolecularcompoundsdonotconductelectricitybecausetheirmoleculesarenotcharged
9. understandthatbondingwithinmoleculesiscovalentand arises from the electrostatic attraction between the nuclei of the atoms and the electrons shared between them
10. understandthatcovalentbondsarestrong,incontrasttotheweakforcesofattractionbetweensmallcovalentmolecules
11. translatebetweenrepresentationsofmoleculesincludingmolecularformulae,2-Ddiagramsinwhichcovalentbondsarerepresentedbylines,and3-Ddiagramsfor:
a. elementsthataregasesat20°C b. simplemolecularcompounds.
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Module C5: Chemicals of the natural environmentC5.2 What reactions happen in the hydrosphere?1. recallthattheEarth’shydrosphere(oceans,seas,lakesandrivers)consistsmainlyofwater
withsomedissolvedcompounds,calledsalts2. understandthattheionsincrystalsofasolidioniccompoundarearrangedinaregularway
formingalattice3. understandthationsinacrystalareheldtogetherbyforcesofattractionbetweenoppositely
chargedionsandthatthisiscalledionicbonding4. understandhowthephysicalpropertiesofsolidioniccompounds(meltingpoint,boiling
point,electricalconductivity)relatetotheirbondingandgiant,three-dimensionalstructures5. describewhathappenstotheionswhenanioniccrystaldissolvesinwater6. explainthationiccompoundsconductelectricitywhendissolvedinwaterbecausetheions
arechargedandtheyareabletomovearoundindependentlyinthesolution7. work out the formulae for salts in seawater given the charges on ions (for example
sodium chloride, magnesium chloride, magnesium sulfate, sodium sulfate, potassium chloride and potassium bromide)
8. understandthattheionsinanioniccompoundcanbedetectedandidentifiedbecausetheyhavedistinctpropertiesandtheyformcompoundswithdistinctproperties
9. understandthataninsolublecompoundmayprecipitateonmixingtwosolutionsofioniccompounds
10. be able to write ionic equations for precipitation reactions when given appropriate information
11. interpret given information on solubility to predict chemicals that precipitate on mixing solutions of ionic compounds
12. understandthatsomemetalionscanbeidentifiedinsolutionbyaddingalkalibecausetheyforminsolublehydroxideswithcharacteristiccolours
13. interprettheresultsofaddingaqueoussodiumhydroxidetosolutionsofsalts,givenadatasheetoftestsforpositivelychargedionsandappropriateresults
Candidates will be given a qualitative analysis data sheet showing tests for positively charged ions (as in Appendix G) with the examination paper
14. understandthatsomenegativeionsinsaltscanbeidentifiedinsolutionbyaddingareagentthatreactswiththeionstoformaninsolublesolid
15. interprettheresultsoftestsforcarbonate,chloride,bromide,iodideandsulfateionsgivenadatasheetoftestsfornegativelychargedionsandappropriateresults(usingdiluteacid,limewater,silvernitrateandbariumchlorideorbariumnitrateasthereagents).
Candidates will be given a qualitative analysis data sheet showing tests for negatively charged ions (as in Appendix G) with the examination paper
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Module C5: Chemicals of the natural environmentC5.3 What types of chemicals make up the Earth’s lithosphere?1. recallthattheEarth’slithosphere(therigidouterlayeroftheEarthmadeupofthecrustand
thepartofthemantlejustbelowit)ismadeupofamixtureofminerals2. recallthatdiamondandgraphiteareminerals,bothofwhicharecomposedofcarbonatoms3. explainthepropertiesofdiamondintermsofagiantstructureofatomsheldtogetherby
strongcovalentbonding(forexample,meltingpoint,boilingpoint,hardness,solubilityandelectricalconductivity)
4. understandhowthegiantstructureofgraphitediffersfromthatofdiamond,andhowthisaffectsitsproperties
5. recallthatsilicon,oxygenandaluminiumareveryabundantelementsintheEarth’scrust6. interpretdataabouttheabundancesofelementsinrocks7. recallthatmuchofthesiliconandoxygenispresentintheEarth’scrustasthecompound
silicondioxide8. understandthatsilicondioxideisanothergiantcovalentcompoundandsohasproperties
similartodiamond.
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Module C5: Chemicals of the natural environmentC5.4 How can we extract useful metals from minerals?1. recallthatoresarerocksthatcontainvaryingamountsofmineralsfromwhichmetalscanbe
extracted2. understandthatforsomeminerals,largeamountsoforeneedtobeminedtorecoversmall
percentagesofvaluableminerals(forexample,incoppermining)3. recallthatzinc,ironandcopperaremetalsthatcanbeextractedbyheatingtheiroxideswith
carbon,andwritesimplewordequationsforthesereactions Technical details not required4. understandthatwhenametaloxidelosesoxygenitisreduced,whilethecarbongains
oxygenandisoxidised5. understandthatsomemetalsaresoreactivethattheiroxidescannotbereducedbycarbon6. writewordequationswhengivenappropriateinformation7. interpretsymbolequations,includingthenumberofatomsofeachelement,thenumber
ofmoleculesofeachelementorcovalentcompoundandthenumberof‘formulas’ofioniccompounds,inreactantsandproducts
In this context, ‘formula’ is used in the case of ionic compounds as an equivalent to molecules in covalent compounds; the concept of the mole is not covered in the specification
8. balance unbalanced symbol equations9. write balanced equations, including the state symbols (s), (l ), (g) and (aq), when given
appropriate information10. recallthestatesymbols(s),(l ),(g)and(aq)andunderstandtheiruseinequations11. usethePeriodicTabletoobtaintherelativeatomicmassesofelements12. userelativeatomicmassestocalculaterelativeformulamasses13. calculatethemassofanelementinthegramformulamassofacompound14. calculate the mass of the metal that can be extracted from a mineral given its formula
or an equation15. describeelectrolysisasthedecompositionofanelectrolytewithanelectriccurrent16. understandthatelectrolytesincludemoltenioniccompounds17. describewhathappenstotheionswhenanioniccrystalmelts18. understandthat,duringelectrolysis,metalsformatthenegativeelectrodeandnon-metals
formatthepositiveelectrode19. describetheextractionofaluminiumfromaluminiumoxidebyelectrolysis20. understand that during electrolysis of molten aluminium oxide, positively charged
aluminium ions gain electrons from the negative electrode to become neutral atoms21. understand that during electrolysis of molten aluminium oxide, negatively charged
oxide ions lose electrons to the positive electrode to become neutral atoms which then combine to form oxygen molecules
22. use ionic theory to explain the changes taking place during the electrolysis of a molten salt to account for the conductivity of the molten salt and the changes at the electrodes
23. understandthattheusesofmetalsarerelatedtotheirproperties(limitedtostrength,malleability,meltingpointandelectricalconductivity)
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C5.4 How can we extract useful metals from minerals?
24. explainthephysicalpropertiesofhighstrengthandhighmeltingpointofmetalsintermsofagiantstructureheldtogetherbystrongbonds(metallicbonding)
25. understand that in a metal crystal there are positively charged ions, held closely together by a sea of electrons that are free to move, and use this to explain the physical properties of metals, including malleability and conductivity
26. evaluate,givenappropriateinformation,theimpactsontheenvironmentthatcanarisefromtheextraction,useanddisposalofmetals.
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Synthesisprovidesmanyofthechemicalsthatpeopleneedforfoodprocessing,healthcare,cleaninganddecorating,modernsportingmaterialsandmanyotherproducts.Thechemicalindustrytodayisdevelopingnewprocessesformanufacturingthesechemicalsmoreefficientlyandwithlessimpactontheenvironment.
Inthiscontext,themoduleexploresrelatedquestionsthatchemistshavetoanswer:‘Howmuch?’and‘Howfast?’inthecontextofthechemicalindustry.Quantitativeworkincludesthecalculationofyieldsfromchemicalequationsandthemeasurementofratesofreaction.
Afurtherdevelopmentofionictheoryshowshowchemistsusethistheorytoaccountforthecharacteristicbehavioursofacidsandalkalis.Energyleveldiagramsareusedtodescribetheexothermicandendothermicnatureofchemicalreactions.
Thismoduleoffersopportunitiestodevelopmathematicsskills.Forexample:
• carryoutcalculationsusingexperimentaldata,includingfindingthemeanandtherange
• carryoutcalculationstofindpercentageyield
• useideasofratiosinthecontextofformulaeofioniccompounds
• plot,drawandinterpretgraphsandchartsfromcandidates’ownandsecondarydata
• useanequationforcalculatingtherateofareaction
• useideasaboutcorrelationinthecontextofratesofreaction
• balanceequations
• calculatereactingmassesandyield.
Overview
3.5.3 Module C6: Chemical synthesis
TopicsC6.1 ChemicalsandwhyweneedthemThescaleandimportanceofthechemicalindustry;acids,alkalisandtheirreactionsNeutralisationexplainedintermsofionsC6.2 Planning,carryingoutandcontrollingachemicalsynthesisPlanningchemicalsynthesesProceduresformakingpureinorganicproductssafelyComparingalternativeroutestothesameproductCalculatingreactingquantitiesandyieldsMeasuringpuritybysimpletitrationControllingtherateofchange
Opportunities for mathematics
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Thismoduleoffersopportunitiesforpracticalworkinteachingandlearning.Forexample:
• reactionsofacids
• reactionsofalkalis
• exothermicandendothermicreactions
• titrationexperiments
• rateofreactionexperiments
• synthesisofasalt.
ThismoduleoffersopportunitiestoillustratetheuseofICTinscience.Forexample:
• loggingandstoringdata,anddisplayingdatainavarietyofformatsforanalysis.
UseofICTinteachingandlearningcaninclude:
• videoclipstoillustratethemanufactureofchemicalsonalarge-scaleinindustry
• usingsensorsanddataloggerstomonitorneutralisationreactionsandtheratesofchemicalchanges.
Opportunities for practical work
Opportunities for ICT
Opportunities for teaching the Ideas about Science
ExamplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopmentinthismoduleinclude:
laS1.1–1.6
laS2.1–2.3,2.6,2.7
Data: their importance and limitations
Cause-effect explanations
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Module C6: Chemical synthesisC6.1 Chemicals and why we need them1. understandtheimportanceofchemicalsynthesistoprovidefoodadditives,fertilisers,
dyestuffs,paints,pigmentsandpharmaceuticals2. interpretinformationaboutthesectors,scaleandimportanceofchemicalsynthesisin
industryandinlaboratories3. recalltheformulaeofthefollowingchemicals:chlorinegas,hydrogengas,nitrogengas,
oxygengas,hydrochloricacid,nitricacid,sulfuricacid,sodiumhydroxide,sodiumchloride,sodiumcarbonate,sodiumnitrate,sodiumsulfate,potassiumchloride,magnesiumoxide,magnesiumhydroxide,magnesiumcarbonate,magnesiumchloride,magnesiumsulfate,calciumcarbonate,calciumchlorideandcalciumsulfate
4. work out the formulae of ionic compounds given the charges on the ions5. work out the charge on one ion given the formula of a salt and the charge on the other
ion6. recallthemainhazardsymbolsandbeabletogivethesafetyprecautionsforhandling
hazardouschemicals(limitedtoexplosive,toxic,corrosive,oxidizing,andhighlyflammable) See Appendix H for guidance on recent changes to hazard labelling7. recallexamplesofpureacidiccompoundsthataresolids(citricandtartaricacids),liquids
(sulfuric,nitricandethanoicacids)orgases(hydrogenchloride)8. recallthatcommonalkalisincludethehydroxidesofsodium,potassiumandcalcium9. recallthepHscale10. recalltheuseoflitmuspaper,universalindicatorandpHmeterstodetectacidityand
alkalinity,andtheuseofuniversalindicatorandpHmeterstomeasurepH11. recallthecharacteristicreactionsofacidsthatproducesalts,toincludethereactionswith
metalsandtheiroxides,hydroxidesandcarbonates12. writewordequationswhengivenappropriateinformation13. interpretsymbolequations,includingthenumberofatomsofeachelement,thenumber
ofmoleculesofeachelementorcovalentcompoundandthenumberof‘formulas’ofioniccompounds,inreactantsandproducts
In this context, ‘formula’ is used in the case of ionic compounds as an equivalent to molecules in covalent compounds; the concept of the mole is not covered in the specification
14. balance unbalanced symbol equations15. write balanced equations, including the state symbols (s), (l ), (g) and (aq), to describe
the characteristic reactions of acids and other reactions when given appropriate information
16. recallthestatesymbols(s),(l ),(g)and(aq)andunderstandtheiruseinequations17. recallthatthereactionofanacidwithanalkalitoformasaltisaneutralisationreaction18. explainthatacidiccompoundsproduceaqueoushydrogenions,H+(aq),whentheydissolve
inwater19. explainthatalkalinecompoundsproduceaqueoushydroxideions,OH–(aq),whenthey
dissolveinwater20. writedownthenameofthesaltproducedgiventhenamesoftheacidandalkali
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C6.1 Chemicals and why we need them
21. write down the formula of the salt produced given the formulae of the acid and alkali22. explainthatduringaneutralisationreaction,thehydrogenionsfromtheacidreactwith
hydroxideionsfromthealkalitomakewater: H+(aq)+OH−(aq)→H2O(l )23. understandthetermsendothermicandexothermic24. useandinterpretsimpleenergyleveldiagramsforendothermicandexothermicreactions25. understandtheimportanceoftheenergychangeduringareactiontothemanagementand
controlofachemicalreaction.
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Module C6: Chemical synthesisC6.2 Planning, carrying out and controlling a chemical synthesis1. identifythestagesinagivenchemicalsynthesisofaninorganiccompound(limitedtoacid-
alkalireactions),including: a. choosingthereactionorseriesofreactionstomaketherequiredproduct b. carryingoutariskassessment c. working out the quantities of reactants to use d. carryingoutthereactioninsuitableapparatusintherightconditions(suchas
temperature,concentration) e. separatingtheproductfromthereactionmixture(limitedtofiltration) f. purifyingtheproduct(limitedtoevaporation,crystallisationanddryinginanovenor
desiccator) g. measuringtheyieldandcheckingthepurityoftheproduct(bytitration)2. understandthepurposeofthesetechniques:dissolving,crystallisation,filtration,
evaporation,dryinginanovenordesiccator3. understandtheimportanceofpurifyingchemicalsandcheckingtheirpurity4. understandthatabalancedequationforachemicalreactionshowstherelativenumbersof
atomsandmoleculesofreactantsandproductstakingpartinthereaction5. understandthattherelativeatomicmassofanelementshowsthemassofitsatomrelative
tothemassofotheratoms6. usethePeriodicTabletoobtaintherelativeatomicmassesofelements7. calculatetherelativeformulamassofacompoundusingtheformulaandtherelativeatomic
massesoftheatomsitcontains8. substituterelativeformulamassesanddataintoagivenmathematicalformulatocalculate
reactingmassesand/orproductsfromachemicalreaction9. calculate the masses of reactants and products from balanced equations10. calculatepercentageyieldsgiventheactualandthetheoreticalyield11. describehowtocarryoutanacid-alkalititrationaccurately,whenstartingwithasolutionora
solidtobedissolvedtomakeupasolution Making up of standard solutions is not required12. substituteresultsinagivenmathematicalformulatointerprettitrationresultsquantitatively13. understandwhyitisimportanttocontroltherateofachemicalreaction(toincludesafety
andeconomicfactors)14. explainwhatismeantbytheterm‘rateofchemicalreaction’15. describemethodsforfollowingtherateofareaction(forexample,bycollectingagas,
weighingthereactionmixtureorobservingtheformationorlossofacolourorprecipitate)16. interpretresultsfromexperimentsthatinvestigateratesofreactions17. understandhowreactionratesvarywiththesizeofsolidparticles,theconcentrationof
solutionsofchemicalsandthetemperatureofthereactionmixture A qualitative treatment only is expected
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C6.2 Planning, carrying out and controlling a chemical synthesis
18. understandthatcatalystsspeedupchemicalreactionswhilenotbeingusedupinthereaction
19. interpretinformationaboutthecontrolofratesofreactioninchemicalsynthesis20. usesimpleideasaboutcollisionstoexplainhowchemicalreactionstakeplace21. usesimplecollisiontheoryandideasaboutcollisionfrequencytoexplainhowratesof
reactiondependonthesizeofsolidparticlesandontheconcentrationofsolutionsofdissolvedchemicals.
The effect of temperature on collision frequency is not considered since activation energy has a greater influence
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UnitA182istheunitwithinGCSEAdditionalScienceAwherethephysicscontentisassessed.ItassessesthecontentofModules P4, P5 and P6togetherwiththeIdeasaboutScience.
3.6 Summary of Unit A182: Physics A Modules P4, P5, P6
Simplebutcounterintuitiveconceptsofforcesandmotion,developedbyGalileoandNewton,cantransformyoungpeople’sinsightintoeverydayphenomena.Theseideasalsounderpinanenormousrangeofmodernapplications,includingspacecraft,urbanmasstransitsystems,sportsequipmentandridesatthemeparks.
Thismodulestartsbylookingathowspeedismeasuredandrepresentedgraphicallyandtheideaofvelocity(asdistinctfromspeed).
Thesecondtopicintroducestheideaofforces:identifying,describingandusingforcestoexplainsimplesituations.Thisisfurtherdevelopedinthethirdtopicwhereresultantforcesandchangesinmomentumaredescribed.
Thefinaltopicconsidershowwecanexplainmotionintermsofenergychanges.
Overview
3.6.1 Module P4: Explaining motion
TopicsP4.1 Howcanwedescribemotion?
CalculationofspeedVelocityAccelerationGraphicalrepresentationsofspeedandvelocityP4.2 Whatareforces?Theidentificationofforcesand‘partner’forcesP4.3 Whatistheconnectionbetweenforcesandmotion?
ResultantforcesandchangeinmomentumRelatingmomentumtoroadsafetymeasuresP4.4 Howcanwedescribemotionintermsofenergychanges?
WorkdoneChangesinenergyGPEandKELossesduetoairresistanceandfriction
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Thismoduleoffersopportunitiestodevelopmathematicsskills.Forexample:
• carryoutcalculationsusingexperimentaldata,includingfindingthemeanandtherange
• useideasofproportion
• plot,drawandinterpretgraphsfromcandidates’ownandsecondarydata
• useequations,includingappropriateunitsforphysicalquantities
• useideasaboutprobabilityinthecontextofrisk.
Thismoduleoffersopportunitiesforpracticalworkinteachingandlearning.Forexample:
• usedataloggingtoinvestigatemotion
• investigatethebehaviourofcollidingand‘exploding’objects
• investigatetheeffectofdifferentcombinationsofsurfacesonthefrictionalforces
• investigatethemotionofobjectsinfreefallandtheeffectsofairresistance.
ThismoduleoffersopportunitiestoillustratetheuseofICTinscience.Forexample:
• computerprogramsthatcontrolthemotionofspacecraft
• useofcomputersforcollecting,storinganddisplayingdataonforcesinsimulatedvehiclecollisions
• computer-enhanceduseofradartopredictflightpathsofaircraft.
UseofICTinteachingandlearningcaninclude:
• videoclipstoprovidecontextsforlearningaboutforcesandmotion
• animationstoillustrateinteractiveforcepairsinvarioussituations
• animationstoshowthemeaningofdistance-timeandothergraphs
• sensorsanddataloggerstocollectmeasurementsofmovementforanalysis
• modellingsoftwaretoanalysemotion.
Opportunities for mathematics
Opportunities for practical work
Opportunities for ICT
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Opportunities for teaching the Ideas about Science
ExamplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopmentinthismoduleinclude:
laS1.1–1.6
laS2.1–2.6,2.7
laS3.1–3.4
Data: their importance and limitations
Cause-effect explanations
Developing scientific explanations
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Module P4: Explaining motionP4.1 How can we describe motion?1. applythefollowingequationtosituationswhereanaveragespeedisinvolved:
speed(m/s)=distancetravelled(m)––––––––––––––––––
timetaken(s)
2. distinguishbetweenaveragespeedandinstantaneousspeed(ineffect,anaverageoverashorttimeinterval)forexamplesofmotionwherespeedischanging
3. understand that the displacement of an object at a given moment is its net distance from its starting point together with an indication of direction
4. drawandinterpretadistance-time(or displacement-time)graphforanobjectthatis: a. stationary b. movingatconstantspeed c. moving with increasing or decreasing speed5. interpretasteepergradientofadistance-timegraphasahigherspeed6. calculate a speed from the gradient of a straight section of a distance-time graph7. drawandinterpretaspeed-timegraphforanobjectthatis: a. stationary b. movinginastraightlinewithconstantspeed c. movinginastraightlinewithsteadilyincreasingordecreasingspeed(butnochange
ofdirection)8. understandthatinmanyeverydaysituations,accelerationisusedtomeanthechangein
speedofanobjectinagiventimeinterval9. recallthattheinstantaneousvelocityofanobjectisitsinstantaneousspeedtogetherwithan
indicationofthedirection10. understand that the velocity of an object moving in a straight line is positive if it is
moving in one direction and negative if it is moving in the opposite direction11. draw and interpret a velocity-time graph for an object that is: a. stationary b. moving in a straight line with constant speed c. moving in a straight line with steadily increasing or decreasing speed
(including situations involving a change of direction)12. calculate the acceleration from the gradient of a velocity–time graph (or from a speed-
time graph in situations where direction of motion is constant)13. calculateaccelerationusingtheequation:
acceleration(m/s2)=changeinvelocity(m/s)–––––––––––––––––––
timetaken(s)
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Module P4: Explaining motionP4.2 What are forces?1. recallthataforcearisesfromaninteractionbetweentwoobjects2. understandthatwhentwoobjectsinteract,bothalwaysexperienceaforceandthatthese
twoforcesformaninteractionpair3. insimpleeverydaysituations: a. identifyforcesarisingfromaninteractionbetweentwoobjects b. identifythe‘partner’ofagivenforce(i.e.theotherforceoftheinteractionpair) c. specify,foreachforce,theobjectwhichexertsit,andtheobjectonwhichitacts d. usearrowstoshowthesizesanddirectionsofforcesacting4. understandthatthetwoforcesinaninteractionpairareequalinsizeandoppositein
direction,andthattheyactondifferentobjects5. describetheinteractionbetweentwosurfaceswhichslide(ortendtoslide)relativetoeach
other:eachsurfaceexperiencesaforceinthedirectionthatprevents(ortendstoprevent)relativemovement;thisinteractioniscalledfriction
6. describetheinteractionbetweenanobjectandahorizontalsurfaceitisrestingon:theobjectpushesdownonthesurface,thesurfacepushesupontheobjectwithanequalforce,andthisiscalledthereactionofthesurface
7. recallthatfrictionandthereactionofasurfaceariseinresponsetotheactionofanappliedforce,andtheirsizematchestheappliedforceuptoalimit
8. usetheideasoffrictionandreactiontoexplainsituationssuchasthedrivingforceonvehiclesand walking
9. usetheideaofapairofequalandoppositeforcestoexplaininoutlinehowrocketsandjetenginesproduceadrivingforce.
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Module P4: Explaining motionP4.3 What is the connection between forces and motion?1. interpretsituationsinwhichseveralforcesactonanobject2. understandthattheresultantforceonanobjectisthesumofalltheindividualforcesacting
onit,takingtheirdirectionsintoaccount3. understandthatifaresultantforceactsonanobject,itcausesachangeofmomentuminthe
directionoftheforce4. usethedefinition: momentum = mass × velocity (kgm/s) (kg) (m/s)5. understandthatthesizeofthechangeofmomentumofanobjectisproportionaltothesize
oftheresultantforceactingontheobjectandtothetimeforwhichitacts: changeofmomentum = resultantforce × timeforwhichitacts (kgm/s) (N) (s)6. understandhowthehorizontalmotionofobjects(likecarsandbicycles)canbeanalysedin
termsofadrivingforce(producedbytheengineorthecyclist),andacounterforce(duetofrictionandairresistance)
7. understandthatforanobjectmovinginastraightline,ifthedrivingforceis: a. greaterthanthecounterforce,thevehiclewillspeedup b. equaltothecounterforce,thevehiclewillmoveatconstantspeedinastraightline c. smallerthanthecounterforce,thevehiclewillslowdown8. understandthat,insituationsinvolvingachangeinmomentum(suchasacollision),the
longerthedurationoftheimpact,thesmallertheaverageforceforagivenchangeinmomentum
9. useideasaboutforceandmomentumtoexplainroadsafetymeasures,suchascarseat-belts,crumplezones,airbags,andcycleandmotorcyclehelmets
10. understandhowtheverticalmotionofobjects(falling,orinitiallythrownupwards)canbeanalysedintermsoftheforcesacting(gravity,airresistance)
11. understandthat,iftheresultantforceonanobjectiszero,itsmomentumdoesnotchange(ifitisstationary,itstaysatrest;ifitisalreadymoving,itcontinuesataconstantvelocity[asteadyspeedinastraightline]).
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Module P4: Explaining motionP4.4 How can we describe motion in terms of energy changes?1. recallthattheenergyofamovingobjectiscalleditskineticenergy2. recallthatasanobjectisraised,itsgravitationalpotentialenergyincreases,andasitfalls,
itsgravitationalpotentialenergydecreases3. recallthatwhenaforcemovesanobject,itdoeswork4. usetheequation: workdonebyaforce = force × distancemovedinthedirectionoftheforce (joules,J) (newtons,N) (metres,m)5. understandthatwhenworkisdoneonanobject,energyistransferredtotheobjectand
whenworkisdonebyanobject,energyistransferredfromtheobjecttosomethingelse,accordingtotherelationship:
amountofenergytransferred = workdone (joules,J) (joules,J)6. understandthatwhenanobjectisliftedtoahigherpositionabovetheground,workisdone
bytheliftingforce;thisincreasesthegravitationalpotentialenergy7. usetheequation: changeingravitationalpotentialenergy = weight × verticalheightdifference (joules,J) (newtons,N) (metres,m)8. understandthatwhenaforceactingonanobjectmakesitsvelocityincrease,theforcedoes
workontheobjectandthisresultsinanincreaseinitskineticenergy9. understandthatthegreaterthemassofanobjectandthefasteritismoving,thegreaterits
kineticenergy10. usetheequation: kineticenergy = ½ × mass × [velocity]2 (joules,J) (kilograms,kg) ([metrespersecond]2,[m/s]2)11. understandthatiffrictionandairresistancecanbeignored,anobject’skineticenergy
changesbyanamountequaltotheworkdoneonitbyanappliedforce12. understandthatairresistanceorfrictionwillcausethegaininanobject’skineticenergytobe
lessthantheworkdoneonitbyanappliedforceinthedirectionofmotion,becausesomeenergyisdissipatedthroughheating
13. recallthatenergyisalwaysconservedinanyeventorprocess14. calculatethegaininkineticenergy,and the speed,ofanobjectthathasfallenthrougha
givenheight.
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Knownonlybyitseffects,electricityprovidesanidealvehicletoillustratetheuseandpowerofscientificmodels.Duringthecourseofthe20thcentury,electricalengineerscompletelychangedwholesocieties,bydesigningsystemsforelectricalgenerationanddistribution,andawholerangeofelectricaldevices.
Inthismodule,candidateslearnhowscientistsvisualisewhatisgoingoninsidecircuitsandpredictcircuitbehaviour.Theideaofcurrentasaflowofelectronsisintroducedinthefirsttopic.Inthesecondtopic,usefulmodelsofchargemovingthroughcircuitsdrivenbyavoltageandagainstaresistanceareintroduced.Amoregeneralunderstandingofvoltageaspotentialdifferenceisdevelopedinthethirdtopic.
Theconceptsofcurrentandvoltagearefurtherdevelopedinthetopicongenerationofelectricity.Thefinaltopicrelatestheseconceptstopower,andintroducestheideaofefficiencyofelectricalappliances
Candidates will only be expected to consider situations in which the internal resistance of batteries or other electrical power supplies is negligible and can be ignored.
Overview
3.6.2 Module P5: Electric circuits
TopicsP5.1 Electriccurrent–aflowofwhat?
ElectriccurrentasaflowofchargeHowthechargemovesP5.2 Whatdeterminesthesizeofthecurrentinanelectriccircuitandtheenergyittransfers?
VoltageCurrentandresistanceSeriesandparallelcircuitsP5.3 Howdoparallelandseriescircuitswork?
VoltageandhowitbehavesinaseriescircuitCurrentandhowitbehavesinaparallelcircuitP5.4 Howismainselectricityproduced?Howarevoltagesandcurrentsinduced?
HowgeneratorsworkTransformersAlternatingcurrentanddirectcurrentP5.5 Howdoelectricmotorswork?Howmotorsworkandsomeuses
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Thismoduleoffersopportunitiestodevelopmathematicsskills.Forexample:
• carryoutcalculationsusingexperimentaldata,includingfindingthemeanandtherange
• carryoutcalculationsusingfractionsandpercentages
• useideasofproportion
• useideasofratiosinthecontextoftransformers
• useequations,includingappropriateunitsforphysicalquantities
• plot,drawandinterpretgraphsfromcandidates’ownandsecondarydata
• useideasaboutprobabilityinthecontextofrisk.
Thismoduleoffersopportunitiesforpracticalworkinteachingandlearning.Forexample:
• investigatingthebehaviourofelectriccircuits
• makingbothmodelgeneratorsandmotorsandinvestigatingfactorsaffectingtheirbehaviour
• investigatingthebehaviouroftransformers.
ThismoduleoffersopportunitiestoillustratetheuseofICTinscience.Forexample:
• studyingelectricfieldsbetweenchargedparticlesandsurfaces
• usingcomputersimulationstoconstructvirtualcircuitsandtesttheirbehaviour.
UseofICTinteachingandlearningcaninclude:
• modellingsoftwaretoexploreelectriccircuittheory
• animationstoillustratemodelsofelectriccurrentasflowingcharges.
Opportunities for mathematics
Opportunities for practical work
Opportunities for ICT
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Opportunities for teaching the Ideas about Science
ExamplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopmentinthismoduleinclude:
laS1.1–1.6
laS2.1–2.6,2.7
Data: their importance and limitations
Cause-effect explanations
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Module P5: Electric circuitsP5.1 Electric current – a flow of what?1. explainthatwhentwoobjectsarerubbedtogethertheybecomecharged,becauseelectrons
aretransferredfromoneobjecttotheother2. recallthatobjectswithsimilarchargesrepel,andobjectswithoppositechargesattract3. explainsimpleelectrostaticeffectsintermsofattractionandrepulsionofcharges4. recallthatelectronsarenegativelycharged5. recallthatelectriccurrentisaflowofcharge6. recallthatelectriccurrentismeasuredinamperes7. understandthatinanelectriccircuitthemetalconductors(thecomponentsandwires)
containmanychargesthatarefreetomove8. understandthatwhenacircuitismade,thebatterycausesthesefreechargestomove,and
thattheyarenotusedupbutflowinacontinuousloop9. recallthatinmetallicconductorsanelectriccurrentisamovementoffreeelectronsthatare
presentthroughoutsuchmaterials10. understandthatinmetalconductorstherearelotsofchargesfreetomovebutinaninsulator
therearefewchargesfreetomove.11. describehowanammetershouldbeconnectedinacircuittomeasuretheflowofcurrentat
achosenpoint.
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Module P5: Electric circuitsP5.2 What determines the size of the current in an electric circuit and the energy it
transfers?1. recallthatthelargerthevoltageofthebatteryinagivencircuit,thebiggerthecurrent2. recallthatcomponents(forexample,resistors,lamps,motors)resisttheflowofcharge
throughthem3. recallthatthelargertheresistanceinagivencircuit,thesmallerthecurrentwillbe4. recallthattheresistanceofconnectingwiresissosmallthatitcanusuallybeignored5. understandthatwhenelectricchargeflowsthroughacomponent(ordevice),workis
donebythepowersupply,andenergyistransferredfromittothecomponentand/oritssurroundings
6. recallthatpower(inwatts,W)isameasureoftherateatwhichanelectricalpowersupplytransfersenergytoanapplianceordeviceand/oritssurroundings
7. usetheequation: power = voltage × current (watts,W) (volts,V) (amperes,A)8. recallthatresistorsgethotterwhenthereisanelectriccurrentthroughthem,and
understand that this heating effect is caused by collisions between the moving charges and stationary ions in the wire
9. recallthatthisheatingeffectmakesalampfilamenthotenoughtoglow10. describehowtheresistanceofanLDRvarieswithlightintensity11. describehowtheresistanceofathermistor(ntconly)varieswithtemperature12. recogniseandusetheelectricalsymbolsforacell,powersupply,filamentlamp,switch,
LDR,fixedandvariableresistor,thermistor,ammeterandvoltmeter13. understandthattwo(ormore)resistorsinserieshavemoreresistancethaneitheroneonits
own,becausethebatteryhastomovechargesthroughbothofthem14. understandthattwo(ormore)resistorsinparallelprovidemorepathsforchargestomove
alongthaneitherresistoronitsown,sothetotalresistanceisless15. usetheequation:
resistance(ohms,Ω)=voltage(volts,V)
–––––––––––––––––current(amperes,A)
16. describeinwords,orusingasketchgraph,howthecurrentthroughacomponentvarieswithvoltageacrossitwhentheresistancestaysconstant.
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Module P5: Electric circuitsP5.3 How do parallel and series circuits work?1. describehowavoltmetershouldbeconnectedtomeasurethepotentialdifferencebetween
anytwochosenpoints2. recallthatthevoltageacrossabattery(measuredinV)providesameasureofthe‘push’of
thebatteryonthechargesinthecircuit3. recallthatpotentialdifferenceisanothertermforvoltage4. relatethepotentialdifferencebetweentwopointsinthecircuittotheworkdoneon,orby,a
givenamountofchargeasitmovesbetweenthesepoints5. describetheeffectonpotentialdifferenceandcurrentofaddingfurtheridenticalbatteriesin
seriesand in parallelwithanoriginalsingleone6. understandthatwhentwo(or more)componentsareconnectedinseriestoabattery: a. thecurrentthrougheachcomponentisthesame b. thepotentialdifferencesacrossthecomponentsadduptothepotentialdifference
acrossthebattery(because the work done on each unit of charge by the battery must equal the work done by it on the circuit components)
c. thepotentialdifferenceislargestacrossthecomponentwiththegreatestresistance,because more work is done by the charge moving through a large resistance than through a small one
d. a change in the resistance of one component (variable resistor, LDR or thermistor) will result in a change in the potential differences across all the components
7. understandthatwhenseveralcomponentsareconnectedinparalleldirectlytoabattery: a. the potential difference across each component is equal to the potential
difference of the battery b. the current through each component is the same as if it were the only
component present c. thetotalcurrentfrom(andbackto)thebatteryisthesumofthecurrentsthrough
eachoftheparallelcomponents d. thecurrentislargestthroughthecomponentwiththesmallestresistance,because
the same battery voltage causes a larger current to flow through a smaller resistance than through a bigger one.
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Module P5: Electric circuitsP5.4 How is mains electricity produced? How are voltages and currents induced?1. recallthatmainselectricityisproducedbygenerators2. recallthatgeneratorsproduceavoltagebyaprocesscalledelectromagneticinduction3. understandthatwhenamagnetismovingintoacoilofwireavoltageisinducedacrossthe
endsofthecoil4. understandthatifthemagnetismovingoutofthecoil,ortheotherpoleofthemagnetis
movingintoit,thereisavoltageinducedintheoppositedirection5. understandthatiftheendsofthecoilareconnectedtomakeaclosedcircuit,acurrentwill
flowroundthecircuit6. understandthatachangingmagneticfieldcausedbychangesinthecurrentinonecoilof
wirecaninduceavoltageinaneighbouringcoil7. describetheconstructionofatransformerastwocoilsofwirewoundonanironcore8. understand that a changing current in one coil of a transformer will cause a changing
magnetic field in the iron core, which in turn will induce a changing potential difference across the other transformer coil
9. recallthatatransformercanchangethesizeofanalternatingvoltage10. use the equation:
voltage across primary coil
––––––––––––––––––––––––––voltage across secondary coil =
number of turns in primary coil–––––––––––––––––––––––––––––number of turns in secondary coil
11. describehow,inagenerator,amagnetorelectromagnetisrotatedwithinacoilofwiretoinduceavoltageacrosstheendsofthecoil
12. understandthatthesizeofthisinducedvoltagecanbeincreasedby: a. increasingthespeedofrotationofthemagnetorelectromagnet b. increasingthestrengthofitsmagneticfield c. increasingthenumberofturnsonthecoil d. placinganironcoreinsidethecoil13. describe how the induced voltage across the coil of an a.c. generator (and hence
the current in an external circuit) changes during each revolution of the magnet or electromagnet
14. understandthatwhenthecurrentisalwaysinthesamedirection,itisadirectcurrent(d.c.),e.g.thecurrentfromabattery
15. recallthatmainselectricityisana.c.supply16. understand that a.c. is used because it is easier to generate than d.c., and is easier
and simpler to distribute over long distances17. recallthatthemainsdomesticsupplyintheUKis230volts.
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Module P5: Electric circuitsP5.5 How do electric motors work?1. understandthatacurrent-carryingwireorcoilcanexertaforceonapermanentmagnet,or
onanothercurrent-carryingwireorcoilnearby2. understandthatacurrent-carryingwire,ifplacedinamagneticfieldwhoselinesofforceare
atright-anglestothewire,experiencesaforceatrightanglestoboththecurrentdirectionandthelinesofforceofthefield
3. recallthatacurrent-carryingwirethatisparalleltothelinesofforceofamagneticfieldexperiencesnoforce
4. explainhowthemotoreffectcanresultinaturningforceonarectangularcurrent-carryingcoilplacedinauniformmagneticfield
5. understandthatthemotoreffectcanbeusedtoproducecontinuousrotationofthecoil,byusingacommutatortoensurethatthedirectionofthecurrentinthecoilisreversedatanappropriatepointineachrevolution
6. explaintheroleanduseofmotorsindevicesincludingdomesticappliances,harddiscdrives,DVDplayersandelectricmotorvehicles.
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Theterms‘radiation’and‘radioactivity’areofteninterchangeableinthepublicmind.Becauseofitsinvisibility,radiationiscommonlyfeared.Amoreobjectiveevaluationofrisksandbenefitsisencouragedthroughdevelopinganunderstandingofthemanypracticalusesofradioactivematerials.
Themodulebeginsbyconsideringtheevidenceofanuclearmodeloftheatom,includingRutherford’salphaparticlescatteringexperiment.ThistopicthenusesideasaboutfusionandnuclearenergytointroduceEinstein’sequation.Thepropertiesofalpha,betaandgammaradiationareinvestigatedandideasabouthalf-lifearedeveloped.
Thepropertiesofionisingradiationleadtoaconsiderationofsomeofitsmanyusesandalsorisks,includingnuclearfission.
Throughtheuseofradioactivematerialinthehealthsector,candidateslearnaboutitsharmfuleffectonlivingcellsandhowitcanbehandledsafely.Inthecontextofhealthrisksassociatedwithirradiationand/orcontaminationbyradioactivematerial,theyalsolearnabouttheinterpretationofdataonrisk.
Thismoduleoffersopportunitiestodevelopmathematicsskills.Forexample:
• developasenseofscaleinthecontextofthesizeoftheconstituentsofanatom
• carryoutcalculationsusingexperimentaldata,includingfindingthemeanandtherange
• carryoutcalculationsusingfractionsinhalf-lifecalculations
• plot,drawandinterpretgraphsandchartsfromcandidates’ownandsecondarydata
• useideasaboutprobabilityinthecontextofrisk.
Overview
3.6.3 Module P6: Radioactive materials
TopicsP6.1 Whyaresomematerialsradioactive?
StructureoftheatomNuclearfusionAlpha,betaandgammaradiationHalf-lifeP6.2 Howcanradioactivematerialsbeusedandhandledsafely,includingwastes?
BackgroundradiationUsesofradiationNuclearfissionandnuclearpowerstations
Opportunities for mathematics
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Thismoduleoffersopportunitiesforpracticalworkinteachingandlearning.Forexample:
• investigationsofthepropertiesofionisingradiations
• half-lifeofradioactivematerials
• modellinghalf-life,usingICTordicethrowing.
ThismoduleoffersopportunitiestoillustratetheuseofICTinscience.Forexample:
• computertomographyusedwithgammaimaging
• theroleofcomputersinremotehandlingofhighlyradioactivewaste.
UseofICTinteachingandlearningcaninclude:
• dataloggingtoshowdecayofprotactinium
• animationstoillustrateatomicstructureanddecay
• videoclipstoillustratekeyideasofriskinthecontextofradioactivematerials
• animationstoillustratekeyprocessesinpowerstations.
Opportunities for practical work
Opportunities for ICT
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Opportunities for teaching the Ideas about Science
ExamplesofIdeasaboutScienceforwhichthereareparticularopportunitiesforintroductionordevelopmentinthismoduleinclude:
laS1.1–1.6
laS2.1–2.6,2.7
laS5.1–5.5,5.6,5.7
laS6.1,6.3,6.4
Data: their importance and limitations
Risk
Cause-effect explanations
Making decisions about science and technology
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Module P6: Radioactive materialsP6.1 Why are some materials radioactive?1. recallthatsomeelementsemitionisingradiationallthetimeandarecalledradioactive2. understandthatradioactiveelementsarenaturallyfoundintheenvironment,contributingto
backgroundradiation3. understandthatanatomhasanucleus,madeofprotonsandneutrons,whichissurrounded
byelectrons4. understandthattheresultsoftheRutherford-Geiger-Marsdenalphaparticlescattering
experimentprovidedevidencethatagoldatomcontainsasmall,massive,positiveregion(thenucleus)
5. understand that protons and neutrons are held together in the nucleus by a strong force which balances the repulsive electrostatic force between the protons
6. understandthat,ifbroughtcloseenoughtogether,hydrogennucleicanfuseintoheliumnucleireleasingenergy,andthatthisiscallednuclearfusion
7. understand that Einstein’s equation E = mc2 is used to calculate the energy released during nuclear fusion and fission (where E is the energy produced, m is the mass lost and c is the speed of light in a vacuum)
energy = mass × [speed]2 (joules, J) (kilograms, kg) ([metres per second]2, [m/s]2)8. understand that every atom of any element has the same number of protons but the
number of neutrons may differ, and that forms of the same element with different numbers of neutrons are called isotopes
9. understandthatthebehaviourofradioactivematerialscannotbechangedbychemicalorphysicalprocesses
10. recallthatthreetypesofionisingradiation(alpha,betaandgamma)areemittedbyradioactivematerialsand that alpha particles consist of two protons and two neutrons, and that beta particles are identical to electrons
11. recallthepenetrationpropertiesofeachtypeofradiation12. describe radioactive materials in terms of the instability of the nucleus, radiation
emitted and the element left behind13. complete nuclear equations for alpha and beta decay14. understandthat,overtime,theactivityofradioactivesourcesdecreases15. understandthemeaningofthetermhalf-life16. understandthatradioactiveelementshaveawiderangeofhalf-lifevalues17. carry out simple calculations involving half-life.
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Module P6: Radioactive materialsP6.2 How can radioactive materials be used and handled safely, including wastes?1. understandthationisingradiationcandamagelivingcellsandthesemaybekilledormay
becomecancerous2. understandthationisingradiationisabletobreakmoleculesintobits(calledions),which
can then take part in other chemical reactions3. recalland explainhowionisingradiationcanbeused: a. totreatcancer b. tosterilisesurgicalinstruments c. tosterilisefood d. asatracerinthebody4. recallthatradiationdose(insieverts)(basedonbothamountandtypeofradiation)isa
measureofthepossibleharmdonetoyourbody5. interpretgivendataonriskrelatedtoradiationdose6. understandthatradioactivematerialsexposepeopletoriskbyirradiationandcontamination7. understandthatweareirradiatedandcontaminatedbyradioactivematerialsallthetimeand
recallthemainsourcesofthisbackgroundradiation8. relateideasabouthalf-lifeandbackgroundradiationtothetimetakenforaradioactive
sourcetobecomesafe9. recallcategoriesofpeoplewhoareregularlyexposedtoriskofradiationandthattheir
exposureiscarefullymonitored,includingradiographersandworkersinnuclearpowerstations
10. understandthatanuclearfuelisoneinwhichenergyisreleasedbychangesinthenucleus11. know that in nuclear fission, a neutron splits a large and unstable nucleus (limited to
uranium and plutonium) into two smaller parts, roughly equal in size, releasing more neutrons
12. recallthattheamountofenergyreleasedduringnuclearfissionismuchgreaterthanthatreleasedinachemicalreactioninvolvingasimilarmassofmaterial
13. understand how the nuclear fission process in nuclear power stations is controlled, and use the terms chain reaction, fuel rod, control rod and coolant
14. understandthatnuclearpowerstationsproduceradioactivewaste15. understandthatnuclearwastesarecategorisedashighlevel,intermediatelevelandlow
level,andrelatethistodisposalmethods.
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4Assessment of GCSE Additional Science A
GCSE Additional Science A J242
Unit A162:Biology A Modules B4, B5, B6
25%ofthetotalGCSE1hourwrittenpaper60marks
Thisquestionpaper:• isofferedinFoundationandHigherTiers• assessesModules B4, B5 and B6• usesbothobjectivestyleandfreeresponse
questions(thereisnochoiceofquestions)• assessesthequalityofwrittencommunication.
Unit A172: Chemistry A Modules C4, C5, C6
25%ofthetotalGCSE1hourwrittenpaper60marks
Thisquestionpaper:• isofferedinFoundationandHigherTiers• assessesModules C4, C5 and C6• usesbothobjectivestyleandfreeresponse
questions(thereisnochoiceofquestions)• assessesthequalityofwrittencommunication.
Unit A182: Physics A Modules P4, P5, P6
25%ofthetotalGCSE1hourwrittenpaper60marks
Thisquestionpaper:• isofferedinFoundationandHigherTiers• assessesModules P4, P5 and P6• usesbothobjectivestyleandfreeresponse
questions(thereisnochoiceofquestions)• assessesthequalityofwrittencommunication.
Unit A154: Additional Science A Controlled assessment
25%ofthetotalGCSEControlledassessmentApproximately4.5–6hours64marks
Thisunit:• comprisesaPracticalInvestigationtask• isassessedbyteachers,internallystandardised
andthenexternallymoderatedbyOCR• assessesthequalityofwrittencommunication.
4.1 Overview of the assessment in GCSE Additional Science A
ForGCSEAdditionalScienceAcandidatesmusttakeunitsA162,A172,A182andA154.B
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4.2 Tiers
AllwrittenpapersareofferedinFoundationTierandHigherTier.FoundationTierpapersassessgradesGtoCandHigherTierpapersassessgradesDtoA*.AnallowedgradeEmaybeawardedontheHigherTiercomponents.
InUnitsA162,A172andA182,candidatesareenteredforanoptionineithertheFoundationTierortheHigherTier.UnitA154(controlledassessment)isnottiered.
CandidatesmayenterforeithertheFoundationTierorHigherTierineachoftheexternallyassessedunits.Soacandidatemaytake,forexample,A162/FandA172/H.
4.3 Assessment objectives (AOs)
Candidatesareexpectedtodemonstratetheirabilityto:
AO1 Recall,selectandcommunicatetheirknowledgeandunderstandingofscience
AO2 Applyskills,knowledgeandunderstandingofscienceinpracticalandothercontexts
AO3 Analyseandevaluateevidence,makereasonedjudgementsanddrawconclusionsbasedonevidence.
4.3.1 AO weightings – GCSE Additional Science A
Therelationshipbetweentheunitsandtheassessmentobjectivesoftheschemeofassessmentisshowninthefollowinggrids:
Unit % of GCSE
AO1 AO2 AO3 Total
UnitsA162,A172andA182 30 34 11 75
UnitA154:Controlledassessment 2 5 18 25
Total 32 39 29 100
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GCSEresultsareawardedonthescaleA*toG.Unitsareawardeda*tog.Gradesareindicatedoncertificates.However,resultsforcandidateswhofailtoachievetheminimumgrade(Gorg)willberecordedasunclassified(Uoru)andthisisnotcertificated.
MostGCSEsareunitisedschemes.Whenworkingoutcandidates’overallgradesOCRneedstobeabletocompareperformanceonthesameunitindifferentserieswhendifferentgradeboundarieshavebeenset,andbetweendifferentunits.OCRusesaUniformMarkScaletoenablethistobedone.
Acandidate’suniformmarkforeachunitiscalculatedfromthecandidate’srawmarkonthatunit.Therawmarkboundarymarksareconvertedtotheequivalentuniformmarkboundary.Marksbetweengradeboundariesareconvertedonaproratabasis.
Whenunitresultsareissued,thecandidate’sunitgradeanduniformmarkaregiven.Theuniformmarkisshownoutofthemaximumuniformmarkfortheunit,e.g.60/100.
ThespecificationisgradedonaUniformMarkScale.Theuniformmarkthresholdsforeachoftheassessmentsareshownbelow:
(GCSE) Unit
Weighting
Maximum Unit
Uniform Mark
Unit Grade
a* a b c d e f g u
25%F 69 – – – 60 50 40 30 20 0
25%H 100 90 80 70 60 50 45 – – 0
25% 100 90 80 70 60 50 40 30 20 0
HigherTiercandidateswhofailtogaina‘d’grademayachievean“allowede”.HigherTiercandidateswhomisstheallowedgrade‘e’willbegradedas‘u’.
Acandidate’suniformmarksforeachunitareaggregatedandgradesforthespecificationaregeneratedonthefollowingscale:
QualificationMax
Uniform Mark
Qualification Grade
A* A B C D E F G U
J242 400 360 320 280 240 200 160 120 80 0
Thewrittenpaperswillhaveatotalweightingof75%andcontrolledassessmentaweightingof25%.
Acandidate’suniformmarkforeachpaperwillbecombinedwiththeuniformmarkforthecontrolledassessmenttogiveatotaluniformmarkforthespecification.Thecandidate’sgradewillbedeterminedbythetotaluniformmark.
4.4 Grading and awarding grades
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4.5 Grade descriptions
Gradedescriptionsareprovidedtogiveageneralindicationofthestandardsofachievementlikelytohavebeenshownbycandidatesawardedparticulargrades.Thedescriptionsmustbeinterpretedinrelationtothecontentinthespecification;theyarenotdesignedtodefinethatcontent.Thegradeawardedwilldependinpracticeupontheextenttowhichthecandidatehasmettheassessmentobjectivesoverall.Shortcomingsinsomeaspectsoftheassessmentmaybebalancedbybetterperformanceinothers.
Thegradedescriptorshavebeenproducedbytheregulatoryauthoritiesincollaborationwiththeawardingbodies.
Candidatesrecall,selectandcommunicatetheirlimitedknowledgeandunderstandingofscience.Theyhavealimitedunderstandingthatscientificadvancesmayhaveethicalimplications,benefitsandrisks.Theyrecognisesimpleinter-relationshipsbetweenscienceandsociety.Theyuselimitedscientificandtechnicalknowledge,terminologyandconventions,showingsomeunderstandingofscaleintermsoftime,sizeandspace.
Theyapplyskills,includinglimitedcommunication,mathematicalandtechnologicalskills,knowledgeandunderstandinginpracticalandsomeothercontexts.Theyshowlimitedunderstandingofthenatureofscienceanditsapplications.Theycanexplainstraightforwardmodelsofphenomena,eventsandprocesses.Usingalimitedrangeofskillsandtechniques,theyanswerscientificquestions,solvestraightforwardproblemsandtestideas.
Candidatesinterpretandevaluatesomequalitativeandquantitativedataandinformationfromalimitedrangeofsources.Theycandrawelementaryconclusionshavingcollectedlimitedevidence.
Candidatesrecall,selectandcommunicatesecureknowledgeandunderstandingofscience.Theydemonstrateunderstandingofthenatureofscience,itslaws,itsapplicationsandtheinfluencesofsocietyonscienceandscienceonsociety.Theyunderstandhowscientificadvancesmayhaveethicalimplications,benefitsandrisks.Theyusescientificandtechnicalknowledge,terminologyandconventionsappropriately,showingunderstandingofscaleintermsoftime,sizeandspace.
Theyapplyappropriateskills,includingcommunication,mathematicalandtechnologicalskills,knowledgeandunderstandinginarangeofpracticalandothercontexts.Theyrecognise,understandandusestraightforwardlinksbetweenhypotheses,evidence,theories,andexplanations.Theyusemodelstoexplainphenomena,eventsandprocesses.Usingappropriatemethods,sourcesofinformationanddata,theyapplytheirskillstoanswerscientificquestions,solveproblemsandtesthypotheses.
Candidatesanalyse,interpretandevaluatearangeofquantitativeandqualitativedataandinformation.Theyunderstandthelimitationsofevidenceanddevelopargumentswithsupportingexplanations.Theydrawconclusionsconsistentwiththeavailableevidence.
4.5.1 Grade F
4.5.2 Grade C
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4.5.3 Grade A
Candidatesrecall,selectandcommunicatepreciseknowledgeanddetailedunderstandingofscienceanditsapplications,andoftheeffectsandrisksofscientificdevelopmentsanditsapplicationsonsociety,industry,theeconomyandtheenvironment.Theydemonstrateaclearunderstandingofwhyandhowscientificapplications,technologiesandtechniqueschangeovertimeandtheneedforregulationandmonitoring.Theyuseterminologyandconventionsappropriatelyandconsistently.
Theyapplyappropriateskills,includingcommunication,mathematicalandtechnologicalskills,knowledgeandunderstandingeffectivelytoawiderangeofpracticalcontextsandtoexplainapplicationsofscience.Theyapplyacomprehensiveunderstandingofpracticalmethods,processesandprotocolstoplanandjustifyarangeofappropriatemethodstosolvepracticalproblems.Theyapplyappropriateskills,includingmathematical,technicalandobservationalskills,knowledgeandunderstandinginawiderangeofpracticalcontexts.Theyfollowproceduresandprotocolsconsistently,evaluatingandmanagingriskandworkingaccuratelyandsafely.
Candidatesanalyseandinterpretcriticallyabroadrangeofquantitativeandqualitativeinformation.Theyreflectonthelimitationsofthemethods,proceduresandprotocolstheyhaveusedandthedatatheyhavecollectedandevaluateinformationsystematicallytodevelopreportsandfindings.Theymakereasonedjudgementsconsistentwiththeevidencetodevelopsubstantiatedconclusions.
4.6 Quality of written communication
Quality of written communicationisassessedinallunitsandisintegratedinthemarkingcriteria.
Candidatesareexpectedto:
• ensurethattextislegibleandthatspelling,punctuationandgrammarareaccuratesothatmeaningisclear
• presentinformationinaformthatsuitsitspurpose
• useanappropriatestyleofwritingand,whereapplicable,specialistterminology.
Questionsassessingqualityofwrittencommunicationwillbeindicatedbytheiconofapencil().
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Controlled assessment in GCSE Additional Science A5
Thissectionprovidesgeneralguidanceoncontrolledassessment:whatcontrolledassessmenttasksare,whenandhowtheyareavailable;howtoplanandmanagecontrolledassessmentandwhatcontrolsmustbeappliedthroughouttheprocess.MoresupportcanbefoundontheOCRwebsite.
Teaching and Learning
Controlledassessmentisdesignedtobeanintegralpartofteachingandlearning.Therearemanyopportunitiesinteachingandlearningtodevelopskillsanduseavarietyofappropriatematerialsandequipment.Theseopportunitiesallowstudentstopractiseawiderangeoftasks,andteacherscandiscussandcommentonperformanceasappropriate.
Whenallnecessaryteachingandlearninghastakenplaceandteachersfeelthatcandidatesarereadyforassessment,candidatescanbegiventheappropriatecontrolledassessmenttask.
AllcontrolledassessmenttasksaresetbyOCRandwillbeavailableforsubmissiononlyinJuneexaminationseries.Eachyearachoiceofsixtaskswillbeoffered;twoforeachsubjectareaofbiology,chemistryandphysics.ThesewillcorrespondtothesametasksavailableforsubmissionforBiologyA(UnitA164),ChemistryA(UnitA174)andPhysicsA(UnitA184).Withineachsubjectarea,oneofthetaskswillalwaysbebasedontheAdditionalScienceAModulesB4–B6,C4–C6andP4–P6.
Eachtaskwillbevalidforsubmissioninasingleexaminationseriesonly,butmaybeundertakenatanypointbetweenreleaseofthetaskbyOCRandtheexaminationseriesforwhichthetaskmustbesubmitted.Centresmustensurethatcandidatesundertakeataskthatisvalidforsubmissionintheyearinwhichthecandidateintendstosubmitit.Theseriesinwhicheachtaskcanbesubmittedwillbeclearlymarkedonthefrontcoverofeachtask.Taskswillnotbevalidforsubmissioninanyexaminationseriesotherthanthatindicated.
Everyyear,sixnewcontrolledassessmenttaskswillbemadeavailableonOCRInterchangefrom1June,twoyearsaheadoftheexaminationseriesforwhichthetasksaretobesubmitted.Thesewillberemoveduponexpiry.GuidanceonhowtoaccesscontrolledassessmenttasksfromOCRInterchangeisavailableontheOCRwebsite:www.ocr.org.uk.
Itisnotnecessaryforallcandidatesfromacentretocarryoutthesametaskfromthechoiceofsixprovided.Staffateachcentrecanchoosewhether:
• allcandidatesfromthecentrecompletethesametask
• allcandidatesinanyteachinggroupcarryoutthesametask,butdifferentgroupsusedifferenttasks
• candidatescompletetasksonanindividualbasis.
Thenumberoftasksattemptedisatthediscretionofthecentre,buttheresultsofonlyonecompletetaskmaybesubmitted.
ThecontrolledassessmentforGCSEAdditionalScienceAcomprisesoneelement:aPracticalInvestigation.
Investigationsarecentraltothenatureofscienceasanevidence-basedactivityandPracticalInvestigationsprovideaneffectiveandvalidassessmentinstrumentforacoursewhichisbothabasisforfurtherstudiesandforpossiblefuturecareersinscience.Theabilityofacandidatetoformulatea
5.1 Introduction to controlled assessment tasks
5.2 Nature of controlled assessment tasks
5.2.1 Introduction to skills assessment
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hypothesisandtoexplainpatternsinresultswillberelatedtotheirknowledgeandunderstandingofthetopic.
ControlledassessmenttasksforGCSEAdditionalScienceAPracticalInvestigationsrequirecandidatesto:
• develophypothesesandplanpracticalwaystotestthemincludingriskassessment
• manageriskswhencarryingoutpracticalwork
• collect,process,analyseandinterpretprimaryandsecondarydata,includingtheuseofappropriatetechnologytodrawevidence-basedconclusions
• reviewmethodologytoassessfitnessforpurpose
• reviewhypothesesinthelightofoutcomes.
PracticalInvestigationsthereforedrawtogethertheskillsofpredictingandplanning,andcollecting,interpreting,evaluatingandreviewingprimaryandsecondarydatawithinthecontextofawholeinvestigation.Candidatesshouldbefamiliarwiththeserequirementsbeforestartinganycontrolledassessmenttask.
Itisexpectedthatcandidateswillbeinvolvedinavarietyofpracticalworkduringthecoursethatwillpreparethemforthisassessment.Thisshouldincludedevelopingtheirabilitiestohandleequipmentandcarryoutpracticalproceduressafely,illustratingscienceprincipleswithrealexperiencesandlearninghowtocarryoutandevaluateinvestigations.
Inaddition,candidates’abilitiestodeviseandevaluatesuitablemethods,todecideonsuitabledatarangesandtoofferexplanationswillbecloselylinkedtotheirunderstandingofsomeIdeasaboutScience,particularly:
• IaS1:Data:theirimportanceandlimitations
• IaS2:Cause-effectexplanations
• IaS3:Developingscientificexplanations
• IaS5:Risk.
CandidatesshouldbeencouragedtouseideasandvocabularyrelatedtotheseIdeasaboutScienceintheirreportsanditisthereforeimportantthatcandidatesarefamiliarwiththeseideasbeforeattemptingtheinvestigation.IdeasaboutSciencearedetailedinSection3.3.
ThetaskstobeusedforthecontrolledassessmentthataresetbyOCRwillbepresentedinawaywhichleavessomefreedomforeachcentretovarytheapproachasappropriate,toallowforcandidatesofdifferentabilitiesandinterests,orfordifferencesinthematerials,equipmentandfacilitiesatdifferentcentres.
Thetasksprovidedwillbeopen-endedandinvestigativeinnature.Theinformationprovidedwitheachtaskwillinclude:
• Information for candidates (1):anintroductiontothetopicoftheinvestigation,tobeissuedtocandidatesatthestartofthetask,placingtheworkintoanappropriatewidercontext
• Information for candidates (2):secondarydataforanalysis,tobeissuedtocandidatesonlyoncompletionofthedatacollectionpartoftheirPracticalInvestigation
• Information for teachers:anoverviewoftheinvestigationincludingnotesonpossibleapproachesandassessmentissuesandguidancefortechnicians.
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Atthestartofacontrolledassessment,candidateswillusetheinformationprovidedtoplanhowtocollectdata,includinganypreliminaryworkrequired,andtodevelopatestablehypothesisbeforecarryingouttheinvestigation.Aftercollectingprimarydataandinterpretingandevaluatingtheresults,candidateswillbeexpectedtoengagewithrelevantsecondarydatatodevelopandevaluatetheirconclusionsfurtherandreviewtheiroriginalhypothesis.Sourcesofsecondarydatacanincludeexperimentalresultsfromothercandidatesintheclassorschool,aswellastextbooksandwebsitesontheinternet.Inaddition,OCRwillprovidesomesecondarydatarelevanttothetasksetforeachPracticalInvestigation.
Thecompletedworkwillbepresentedforassessmentasawrittenreport.
Controlledassessmenttaskswillbeavailableuptotwoyearsaheadoftheexaminationseriesforwhichtheyarevalid,toallowplanningtime.Itisanticipatedthatcandidateswillspendatotalofabout4.5–6hoursinproducingtheworkforthisunit.Candidatesshouldbeallowedsufficienttimetocompletethetask.
Whensupervisingtasks,teachersareexpectedto:
• exercisecontinuingsupervisionofworkinordertomonitorprogressandtopreventplagiarism
• provideguidanceontheuseofinformationfromothersourcestoensurethatconfidentialityandintellectualpropertyrightsaremaintained
• exercisecontinuingsupervisionofpracticalworktoensureessentialcompliancewithHealthandSafetyrequirements
• ensurethattheworkiscompletedinaccordancewiththespecificationrequirementsandcanbeassessedinaccordancewiththespecifiedmarkingcriteriaandprocedures.
Teachersmustnotprovidetemplates,modelanswersorfeedbackondrafts.Candidatesmustproducetheirownindividualresponsestoeachstageandworkindependentlytoproducethereportonthefinalstage(analysis,evaluationandreview).
Suggestedstepsandtimingsareincludedbelow,withguidanceonregulatorycontrolsateachstageoftheprocess.Teachersmustensurethatcontrolrequirementsindicatedbelowaremetthroughouttheprocess.
• Strategy:researchandplanning1.5 – 2 hours
Intheresearchandplanningstage,alimitedlevelofcontrolisrequired.Thismeansthatcandidatescanundertakethispartoftheprocesswithoutdirectteachersupervisionandawayfromthecentre,asrequired.Thismayalsoincludecollectionofsecondarydatawherethisinformstheplanningofthework.Candidatesarealsoabletoworkincollaborationduringthisstage.Duringtheresearchphasecandidatescanbegivensupportandguidance.Teacherscanexplainthetask,adviseonhowthetaskcouldbeapproached,adviseonresourcesandalertthecandidatetokeythingsthatmustbeincludedintheirfinalpieceofwork.However,eachcandidatemustdeveloptheirownindividualresponse.
5.3.1 Research and planning, and collecting data
5.2.2 Summary of tasks in Unit A154
Assessment Task Task Marks Weighting
PracticalInvestigation 64 25%
5.3 Planning and managing controlled assessment
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• Collectingdata1.5 – 2 hours
Inthedatacollectionstage,alimitedlevelofcontrolisrequired.Candidateswillcarryoutpracticalworkunderdirectteachersupervisiontocollectprimarydata.Theymayworkincollaborationduringthisstagebutallcandidatesmustbeactivelyinvolvedanddeveloptheirown,individualresponseindetermininghowbesttocollectandrecordprimarydata.
Secondarydatamayalsobecollectedduringthisstagetosupportorextendtheconclusionstotheinvestigation.However,itisnotpermittedtobasetheassessmentsolelyonsecondarydataor(computer)simulations,orondatarecordedbycandidateswhilstwatchingdemonstrations.
TheOCR-providedsecondarydata,Information for Candidates (2),shouldbegiventocandidatesonlyaftercollectionofprimarydataiscompleted.Thiscanbeusedinadditiontosecondarydatacollectedbythecandidate,ifappropriate.TimeshouldbeallowedforfurthercollectionofsecondarydatafollowingtheissueofInformation for Candidates (2).
• Analysis,evaluationandreview1.5 – 2 hours
Thereportforthisstageisproducedinthecentreunderconditionsofhighcontrol,whichmeansthatcandidatesworkindividuallytocompletetheirreportsunderdirectteachersupervision.Teachersmustbeabletoauthenticatetheworkandtheremustbeacknowledgementandreferencingofanysourcesused.Ifwritingupiscarriedoutoverseveralsessions,workmustbecollectedinbetweeneachsession,includinganyelectronicdatastoragesuchasUSBmemorysticksandrewritableCDs.
Candidatesmustobservethefollowingprocedureswhenproducingtheirfinalpieceofworkforthecontrolledassessmenttasks:
• tables,graphsandspreadsheetsmaybeproducedusingappropriateICT.Theseshouldbeinsertedintothefinalreportattheappropriateplace
• anycopiedmaterialmustbesuitablyacknowledged
• quotationsmustbeclearlymarkedandareferenceprovidedwhereverpossible
• worksubmittedformoderationbyOCRmustbemarkedwiththe:
– centrenumber – centrename – candidatenumber – candidatename – unitcodeandtitle – controlledassessmenttasktitle.
Worksubmittedonpaperformoderationmustbesecuredbytreasurytags.Worksubmittedindigitalformat(CDoronline)mustbeinasuitablefilestructureasdetailedinAppendixAattheendofthisspecification.
5.3.2 Analysis, evaluation and review
5.3.3 Presentation of the final piece of work
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Allcontrolledassessmenttasksaremarkedbycentreassessor(s)usingOCRmarkingcriteriaandguidance.
Thiscorrespondstoamediumlevelofcontrol.
Thestartingpointformarkingthetasksisthemarkingcriteria(seesection5.4.5Marking criteria for controlled assessment tasks).Theseidentifylevelsofperformancefortheskills,knowledgeandunderstandingthatthecandidateisrequiredtodemonstrate.Somefurtherguidanceforeachspecifictaskwillbeprovided,ifappropriate,inthe‘Information for teachers’foreachtask.Beforethestartofthecourse,andforuseatINSETtrainingevents,OCRwillprovideexemplificationthroughrealorsimulatedcandidateworkwhichwillhelptoclarifythelevelofachievementthatassessorsshouldbelookingforwhenawardingmarks.
AstandardmethodofmarkingisusedforthecontrolledassessmenttasksforTwentyFirstCenturyScienceGCSEAdditionalScienceA,basedonagridofhierarchicalmarkingcriteria.Themarkingcriteriaindicatelevelsofresponseandaregeneric,socanbeusedformarkinganyOCR-issuedPracticalInvestigation.Theydefinetheperformancefortheskills,knowledgeandunderstandingthatthecandidateisexpectedtodemonstrateateachlevel.ForeachtasksetbyOCR,furtherguidanceonapplyingthemarkingcriteriainthecontextofthetaskmayalsobegivenintheInformation for teachers,ifappropriate.
Candidates’progressthroughataskisassessedinfivestrands,eachofwhichcorrespondstoadifferenttypeofperformancebythecandidate.Threeofthefivestrandsincludetwodifferentaspectsofthework.Thus,markingisbasedonatotalof8aspects,eachofwhichisshownasadifferentrowinthegridofmarkingcriteria.
Foreachaspect,ahierarchicalsetoffourmarkingcriteriashowstypicalperformanceforcandidatesworkingat1–2,3–4,5–6and7–8marks.Thisprovidesalevelofresponsemarkschemewhereachievementisdividedintofournon-overlappingbands,eachcoveringarangeoftwomarks.
Awardofmarksineachrowofthegridisbasedontheprofessionaljudgementoftheteacherandishierarchical.Thismeansthateachofthecriteriaisconsideredinturn,workingupfromthelowestbandtothehighestbandthatisfullymatchedbythecandidate’sperformance.Onceabandhasbeenreachedwhichisnotfullymatchedbytheworkseen,nohigherbandscanbeconsidered.
Withineachtwo-markband,thehighermarkisavailablewheretheperformancefullymatchesthecriterionforthatmarkband(andallpreceding,lowermarkbands).Thelowermarkisawardedwherethecandidatehaspartially,butnotfully,matchedthiscriterionandhasexceededthecriteriainthepreceding,lowermarkbands.
Wherethereisnoevidenceofengagementwithanaspectofthework,oriftheresponseisnotsufficienttomeritawardofonemark,amarkofzeroisawardedfortheaspect.
Thismethodofmarkingcanbeusedevenwherethereiswidevariationinperformancebetweendifferentaspectsofthework.Weakperformanceononeaspectneednotlimitmarksinotheraspects.
InStrandA,twoalternativeroutestocreditareprovided.Onerowofcriteriaisusedforinvestigationswherethecandidateusesgraphicaldisplayorchartstorevealpatternsinthedata.Theotherrowisusedwherethecandidatehasusedstatisticaloralgebraicmethodstoidentifypatterns.Onlytherowwhichgivesthehighestmarkiscounted.However,therequirementsofthehierarchicalmarking
5.4.2 Using the hierarchical marking criteria
5.4.1 Applying the marking criteria
5.4 Marking and moderating controlled assessment
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criteriacanbesatisfiedbycrossingfromonerowtothenexttodemonstratecontinuousprogressionthroughthisstrand.
Thelevelawardedineachaspectisrecordedonamarkinggrid,whichalsoservesasacoversheetiftheworkiscalledformoderation.
Thetotalfortheassessmentisthesumofalltheaspectmarks,givingamaximumpossiblemarkof64.
Eachpieceofinternallyassessedworkshouldshowhowthemarkshavebeenawardedinrelationtothemarkingcriteria.
Thewritingofcommentsoncandidates’work,andcoversheet,providesameansofcommunicationbetweenteachersduringinternalstandardisationandwiththemoderatoriftheworkformspartofthemoderationsample.
5.4.3 Annotation of candidates’ work
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Thefivestrandsinthemarkschemearedesignedtomatchfivemainstagesintheinvestigation.However,candidatesdonotalwaysfollowthissequencestrictlywhenwritingtheirinvestigationreports,andpositiveachievementshouldbecreditedintheappropriatestrandwhereveritisfoundinthereport.
5.4.4 Overview of marking criteria for controlled assessment tasks
Strand Aspect Notes
Sstrategy
S(a)–formulatingahypothesisorprediction
Candidatesreviewfactorsthatmightaffecttheirresults(thismayincludepreliminarytestsoftheseeffects)andusetheirscientificknowledgetochooseaneffecttostudy,basedonapredictionortestablehypothesis(IaS3).Responsesinthisaspectwillbeinextendedwritingandshouldbeassessedforqualityofwrittencommunicationofthecontent.
S(b)–designoftechniquesandchoiceofequipment
Candidatestestdifferentexperimentalmethodsorapparatus,andjustifythechoicestheymake(IaS1).Theyshowawarenessofsafeworkingpracticesandthehazardsassociatedwithmaterials(IaS5,IaS1-3).Atthehighestlevel,afullriskassessmentisincluded.
Ccollectingdata
C–rangeandqualityofprimarydata
Candidatesmakedecisionsabouttheamountofdatatobecollected,therangeofvaluescovered,andeffectivecheckingforrepeatability(IaS1).
Aanalysis
A–revealingpatternsindata
Toallowaccesstoawiderrangeofactivities,thisstrandhastwoalternativesetsofcriteria.Oneisforthequalityofgraphicaldisplay.Thealternativerowcanbeusedtoawardcreditforstatisticalornumericalanalysisofdata,e.g.speciesdistributionsurveys.
Eevaluation
E(a)–evaluationofapparatusandprocedures
Candidatesshowawarenessofanylimitationsimposedbytheapparatusortechniquesusedandsuggestimprovementstothemethod.
E(b)–evaluationofprimarydata
Candidatesconsidercarefullytherepeatabilityoftheirdata,recogniseoutliersandtreatthemappropriately(IaS1).
Rreview
R(a)–collectionanduseofsecondarydata
Candidatescollectsecondarydata,whichcanbeconsideredtogetherwiththeirownprimarydata,togiveabroaderbasisforconfirmation,adaptationorextensionoftheinitialhypothesisorprediction.
R(b)–reviewingconfidenceinthehypothesis
Candidatesmakeanoverallreviewoftheevidenceinrelationtotheunderlyingscientifictheoryandconsiderhowwellitsupportsthehypothesis,andwhatextraworkmighthelptoimproveconfidenceinthehypothesis(IaS2andIaS3).Qualityofwrittencommunicationshouldbetakenintoaccountinassessingthisaspectofthework.
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55.
4.5
Mar
king
cri
teri
a fo
r co
ntro
lled
asse
ssm
ent
task
s
Markingcriteriaaretobeappliedhierarchically(seesection5.4.2).
Stra
nd/
Asp
ect
01
– 2
mar
ks3
– 4
mar
ks5
– 6
mar
ks7
– 8
mar
ksA
Os
S a
*Makeapredictiontotest,but
withoutanyjustification.The
responsemaybesimplistic,
withfrequenterrorsofspelling,
punctuationorgrammarand
havelittleornouseofscientific
vocabulary.
Suggestatestablepredictionand
justifyitbyreferencetocom
mon
senseorpreviousexperience.
Som
erelevantscientific
termsareused,butspelling,
punctuationandgram
marareof
variablequality.
Considerm
ajorfactorsandrefer
toscientificknow
ledgetomake
atestablehypothesisabouthow
onefactorwillaffecttheoutcom
e.
Informationiseffectively
organisedwithgenerallysound
spelling,punctuationand
gram
mar.S
pecialisttermsare
usedappropriately.
Afterconsiderationofallrelevant
factors,selectoneandpropose
atestablehypothesisand
quantitativepredictionabouthow
itwillaffecttheoutcom
es.The
reportiscom
prehensive,relevant
andlogicallysequenced,w
ith
fullandeffectiveuseofrelevant
scientificterminology.Thereare
few,ifany,grammaticalerrors.
AO1:
2marks
AO2:
4marks
AO3:
2marks
S b
*Followagiventechnique,but
withverylim
itedprecisionor
accuracy.M
akeanappropriate
commentaboutsafeworking.
Selectandusebasicequipment
tocollectalimitedam
ountof
data.C
orrectlyidentifyhazards
associatedwiththeprocedures
used.
Selectandusetechniquesand
equipm
entappropriateforthe
rangeofdatarequired,and
explaintherangeschosen.
Identifyanysignificantrisksand
suggestsom
eprecautions.
Justifythechoiceofequipment
andtechniquetoachievedata
whichispreciseandvalid.
Com
pleteafullandappropriate
riskassessment,identifyingways
ofminimisingrisksassociated
withthework.
AO2:
4marks
AO3:
4marks
C*
Recordaverylimitedam
ount
ofdata(e.g.isolatedindividual
datapointswithnoclearpattern),
coveringonlypartoftherangeof
relevantcases/situations,w
ithno
checkingforrepeatability.Datais
generallyoflow
quality.
Recordanadequateam
ountor
rangeofdata,allowingsome
errorsinunitsorlabelling,
andwithlittlecheckingfor
repeatability.D
ataisofvariable
quality,w
ithsom
eoperatorerror
apparent.
Collectandcorrectlyrecord
datatocovertherangeof
relevantcases/situations,w
ith
regularrepeatsorchecksfor
repeatability.D
ataisofgenerally
goodquality.
Chooseanappropriaterange
ofvaluestotestacrossthe
range,withregularrepeatsand
appropriatehandlingofany
outliers.Checksorprelim
inary
workareincludedtoconfirmor
adapttherangeandnumberof
measurementstoensuredataof
highquality.
AO1:
1mark
AO2:
3marks
AO3:
4marks
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5St
rand
/A
spec
t0
1 –
2 m
arks
3 –
4 m
arks
5 –
6 m
arks
7 –
8 m
arks
AO
s
A*
Displaylimitednumbersof
resultsintables,chartsor
graphs,usinggivenaxesand
scales.
Constructsimplechartsor
graphstodisplaydatainan
appropriateway,allowingsome
errorsinscalingorplotting.
Correctlyselectscalesand
axesandplotdataforagraph,
includinganappropriatelineof
bestfit,orconstructcom
plex
chartsordiagram
se.g.species
distributionmaps.
Indicatethespreadofdata(e.g.
throughscattergraphsorrange
bars)orgiveclearkeysfor
displaysinvolvingmultipledata-
sets.
AO3:
8marks
Selectindividualresultsasa
basisforconclusions.
Carryoutsimplecalculationse.g.
correctcalculationofaverages
fromrepeatedreadings.
Usemathematicalcom
parisons
betweenresultstosupporta
conclusion.
Usecom
plexprocessingto
revealpatternsinthedata
e.g.statisticalmethods,use
ofinverserelationships,or
calculationofgradientofgraphs.
E a
*Makerelevantcom
mentsabout
problemsencounteredwhilst
collectingthedata.
Describethelim
itationsim
posed
bythetechniquesandequipment
used.
Suggest(inoutline)
improvem
entstoapparatusor
techniques,oralternativewaysto
collectthedata;
orexplainwhythemethodused
givesdataofsufficientqualityto
allowaconclusion.
Describeindetailimprovem
ents
totheapparatusortechniques,
oralternativewaystocollectthe
data,andexplainwhytheywould
beanimprovem
ent;orexplain
fullywhynofurtherim
provem
ent
couldreasonablybeachieved.
AO3:
8marks
E b
*Makeaclaimforaccuracy
orrepeatability,butwithout
appropriatereferencetothedata.
Correctlyidentifyindividual
resultswhicharebeyondthe
rangeofexperimentalerror(are
outliers),orjustifyaclaimthat
therearenooutliers.
Usethegeneralpatternofresults
ordegreeofscatterbetween
repeatsasabasisforassessing
accuracyandrepeatabilityand
explainhowthisassessm
entis
made.
Considercriticallythe
repeatabilityoftheevidence,
accountingforanyoutliers.
AO3:
8marks
R a
*Com
pareownexperim
ental
resultswithatleastonepieceof
secondarydataandmakebasic
commentsonsimilaritiesand/
ordifferences.Secondarydata
collectedislimitedinamount
andnotalwaysrelevanttothe
investigation.
Identifyindetailsimilarities
anddifferencesbetweenthe
secondarydataandprim
ary
data.S
econdarydatacollectedis
relevanttotheinvestigationand
sourcesarereferenced,although
thesemaybeincomplete.
Describeandexplainthe
extenttowhichthesecondary
datasupports,extendsand/
orunderminestheprimary
data,andidentifyanyareas
ofincompleteness.Arange
ofrelevantsecondarydata
iscollectedfrom
severalfully
referencedsources.
Assessthelevelsofconfidence
thatcanbeplacedonthe
availabledata,andexplain
thereasonsform
akingthese
assessments.C
ommentonthe
importanceofanysimilaritiesor
differences.
AO1:
1mark
AO2:
1mark
AO3:
6marks
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5St
rand
/A
spec
t0
1 –
2 m
arks
3 –
4 m
arks
5 –
6 m
arks
7 –
8 m
arks
AO
s
R b
*Correctlystatewhetherornotthe
originalpredictionorhypothesis
issupported,withreferenceonly
tocom
monsenseorprevious
experience.Theresponseis
simplistic,w
ithfrequenterrorsin
spelling,punctuationorgrammar
andhaslittleornouseof
scientificvocabulary.
Com
mentonwhethertrendsor
correlationsinthedatasupport
thepredictionorhypothesis
andsuggestw
hybyreference
toappropriatescience.S
ome
relevantscientifictermsare
usedcorrectly,butspelling,
punctuationandgram
marareof
variablequality.
Explaintheextenttowhichthe
hypothesiscanaccountforthe
pattern(s)showninthedata.
Userelevantscienceknowledge
toconcludewhetherthe
hypothesishasbeensupported
ortosuggesthow
itshouldbe
modifiedtoaccountforthedata
morecompletely.Information
isorganisedeffectivelywith
generallysoundspelling,
punctuationandgram
mar.
Specialisttermsareused
appropriately.
Giveadetailedaccountofw
hat
extradatacouldbecollected
toincreaseconfidencein
thehypothesis.Thereportis
comprehensive,relevantand
logicallysequenced,w
ithfulland
effectiveuseofrelevantscientific
terminology.Therearefew,ifany,
gram
maticalerrors.
AO1:
2marks
AO3:
6marks
*0marks=noresponseornoresponseworthyofcredit.
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Eachoftheaspectstobeassessedaddressesoneormoreoftheassessmentobjectivesandtheseareshowninthemarkingcriteria.Theoverallbalanceisshowninthetablebelow.
Teachersmustbeconfidentthattheworktheymarkisthecandidate’sown.Thisdoesnotmeanthatacandidatemustbesupervisedthroughoutthecompletionofallworkbuttheteachermustexercisesufficientsupervision,orintroducesufficientchecks,tobeinapositiontojudgetheauthenticityofthecandidate’swork.
Whereverpossible,theteachershoulddiscusswork-in-progresswithcandidates.Thiswillnotonlyensurethatworkisunderwayinaplannedandtimelymannerbutwillalsoprovideopportunitiesforassessorstocheckauthenticityoftheworkandprovidegeneralfeedback.
Candidatesmustnotplagiarise.Plagiarismisthesubmissionofanother’sworkasone’sownand/orfailuretoacknowledgethesourcecorrectly.Plagiarismisconsideredtobemalpracticeandcouldleadtothecandidatebeingdisqualified.Plagiarismsometimesoccursinnocentlywhencandidatesareunawareoftheneedtoreferenceoracknowledgetheirsources.Itisthereforeimportantthatcentresensurethatcandidatesunderstandthattheworktheysubmitmustbetheirownandthattheyunderstandthemeaningofplagiarismandwhatpenaltiesmaybeapplied.Candidatesmayrefertoresearch,quotationsorevidencebuttheymustlisttheirsources.Therewardsfromacknowledgingsources,andthecredittheywillgainfromdoingso,shouldbeemphasisedtocandidatesaswellasthepotentialrisksoffailingtoacknowledgesuchmaterial.
Bothcandidatesandteachersmustdeclarethattheworkisthecandidate’sown.
• Each candidatemustsignadeclarationbeforesubmittingtheirworktotheirteacher.AcandidateauthenticationstatementthatcanbeusedisavailabletodownloadfromtheOCRwebsite.Thesestatementsshouldberetainedwithinthecentreuntilallenquiriesaboutresults,malpracticeandappealsissueshavebeenresolved.A mark of zero must be recorded if a candidate cannot confirm the authenticity of their work.
• Teachersarerequiredtodeclarethattheworksubmittedforinternalassessmentisthecandidate’sownworkbysendingthemoderatoracentreauthenticationform(CCS160)foreachunitatthesametimeasthemarks.Ifacentrefailstoprovideevidenceofauthentication,we will set the mark for that candidate(s) to Pending (Q) for that component until authentication can be provided.
Assessment Objective TOTAL
AO1: Recall,selectandcommunicatetheirknowledgeandunderstandingofscience. 6
AO2: Applyskills,knowledgeandunderstandingofscienceinpracticalandothercontexts. 12
AO3: Analyseandevaluateevidence,makereasonedjudgmentsanddrawconclusionsbasedonevidence. 46
TOTAL 64
5.4.6 Assessment Objectives (AOs)
5.4.7 Authentication of work
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Itisimportantthatallinternalassessorsofthiscontrolledassessmentworktocommonstandards.Centresmustensurethattheinternalstandardisationofmarksacrossassessorsandteachinggroupstakesplaceusinganappropriateprocedure.
Thiscanbedoneinanumberofways.Inthefirstyear,referencematerialandOCRtrainingmeetingswillprovideabasisforcentres’ownstandardisation.Insubsequentyears,this,orcentres’ownarchivematerial,maybeused.Centresareadvisedtoholdpreliminarymeetingsofstaffinvolvedtocomparestandardsthroughcross-markingasmallsampleofwork.Aftermostmarkinghasbeencompleted,afurthermeetingatwhichworkisexchangedanddiscussedwillenablefinaladjustmentstobemade.
Allworkforcontrolledassessmentismarkedbytheteacherandinternallystandardisedbythecentre.MarksarethensubmittedtoOCRandyourmoderator:refertotheOCRwebsiteforsubmissiondatesofthemarkstoOCR.
Thereshouldbeclearevidencethatworkhasbeenattemptedandsomeworkproduced.Ifacandidatesubmitsnoworkforaninternallyassessedcomponent,thenthecandidateshouldbeindicatedasbeingabsentfromthatcomponent.Ifacandidatecompletesanyworkatallforaninternallyassessedcomponent,thentheworkshouldbeassessedaccordingtotheinternalassessmentobjectivesandmarkinginstructionsandtheappropriatemarkawarded,whichmaybezero.
Thecentreauthenticationform(CCS160)mustbesenttothemoderatorwiththemarks.
Onceyouhavesubmittedyourmarks,yourexamsofficerwillreceiveanemailrequestingamoderationsample.Sampleswillincludeworkfromacrosstherangeofattainmentofthecandidates’work.
Thesampleofworkwhichispresentedtothemoderatorformoderationmustshowhowthemarkshavebeenawardedinrelationtothemarkingcriteriadefinedinsection5.4.5.Eachcandidate’sworkshouldhaveacoversheetattachedtoitwithasummaryofthemarksawardedforthetask.
Whenmakingyourentries,theentryoptionspecifieshowthesampleforeachunitistobesubmitted.Foreachoftheseunits,allcandidateworkmustbesubmittedusingthesame entry option.Itisnotpossibleforcentrestoofferbothoptionsforaunitwithinthesameseries.Youcanchoosedifferentoptionsfordifferentunits.Pleaseseethesection8.2.1forentrycodes.
Thesampleofcandidateworkmustbepostedtothemoderatorwithinthreedaysofreceivingtherequest.Youshoulduseoneofthelabelsprovidedtosendthecandidatework.
Wewouldadviseyoutokeepevidenceofworksubmittedtothemoderator,e.g.copiesofwrittenworkorphotographsofpracticalwork.Youshouldalsoobtainacertificateofpostingforallworkthatispostedtothemoderator.
5.5 Internal standardisation
5.6 Submitting marks and authentication
5.7 Submitting samples of candidate work
5.7.1 Sample requests
5.7.2 Submitting moderation samples via post
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TheOCRRepositoryisasecurewebsiteforcentrestouploadcandidateworkandforassessorstoaccessthisworkdigitally.CentrescanusetheOCRRepositoryforuploadingmarkedcandidateworkformoderation.
CentrescanaccesstheOCRRepositoryviaOCRInterchange,findtheircandidateentriesintheirareaoftheRepository,andusetheRepositorytouploadfiles(singlyorinbulk)foraccessbytheirmoderator.
TheOCRRepositoryallowscandidatestosendevidenceinelectronicfiletypesthatwouldnormallybedifficulttosubmitthroughpostalmoderation;forexamplemultimediaorotherinteractiveunitsubmissions.
TheOCRGCSEAdditionalScienceAunitA154canbesubmittedelectronicallytotheOCRRepositoryviaInterchange:pleasecheckSection8.2.1forunitentrycodesfortheOCRRepository.
TherearethreewaystoloadfilestotheOCRRepository:
1.Centrescanloadmultiplefilesagainstmultiplecandidatesbyclickingon‘Uploadcandidatefiles’intheCandidatestaboftheCandidateOverviewscreen.
2.Centrescanloadmultiplefilesagainstaspecificcandidatebyclickingon‘Uploadfiles’intheCandidateDetailsscreen.
3.Centrescanloadmultipleadministrationfilesbyclickingon‘Uploadadminfiles’intheAdministrationtaboftheCandidateOverviewscreen.
TheOCRRepositoryisseenasafaster,greenerandmoreconvenientmeansofprovidingworkforassessment.Itispartofawiderprogrammebringingdigitaltechnologytotheassessmentprocess,theaimofwhichistoprovidesimplerandeasieradministrationforcentres.
InstructionsforhowtouploadfilestoOCRusingtheOCRRepositorycanbefoundonOCRInterchange.
Thepurposeofmoderationistoensurethatthestandardoftheawardofmarksforworkisthesameforeachcentreandthateachteacherhasappliedthestandardsappropriatelyacrosstherangeofcandidateswithinthecentre.
Atthisstage,ifnecessary,centresmayberequiredtoprovideanadditionalsampleofcandidatework(ifmarksarefoundtobeinthewrongorder)orcarryoutsomere-marking.Ifyoureceivesucharequest,pleaseensurethatyourespondasquicklyaspossibletoensurethatyourcandidates’resultsarenotdelayed.
5.7.3 Submitting the moderation samples via the OCR Repository
5.8 External moderation
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6Support for GCSE Additional Science A
6.1 Free support and training from OCR
Workingincloseconsultationwithteachers,publishersandotherexperts,centrescanexpectahighlevelofsupport,servicesandresourcesforOCRqualifications.
Essential FREE support materials including:
• specimenassessmentmaterialsandmarkschemes
• guidetocontrolledassessment
• samplecontrolledassessmentmaterials
• exemplarcandidateworkandmarkingcommentaries
• teachers’handbook
• sampleschemesofworkandlessonplans
• guidetocurriculumplanning.
Essential support services including:
• INSETtraining–forinformationvisitwww.gcse-science.com
• Interchange–acompletelysecure,freewebsitetohelpcentresreduceadministrativetasksatexamtime
• ActiveResults–detaileditemlevelanalysisofcandidateresults
• Answers@OCR–afreeonlineserviceprovidinganswerstofrequentlyaskedquestionsaboutGCSEScience.
OCRworkswithpublisherstoensurecentrescanaccessachoiceofquality,‘OfficialPublisherPartner’and‘Approvedpublication,’resources,endorsedbyOCRforusewithindividualspecifications.
Youcanbeconfidentthatresourcesbrandedwith‘OfficialPublisherPartner’or‘Approvedpublication’logoshaveundergoneOCR’sthoroughqualityassuranceprocessandareendorsedforusewiththerelevantspecification.
TheseendorsementsdonotmeanthatthematerialsaretheonlysuitableresourcesavailableornecessarytoachieveanOCRqualification.Allresponsibilityforthecontentofthepublishedresourcesrestswiththepublisher.
6.2 OCR endorsed resources
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WehavebeenworkingcloselywithOxfordUniversityPress,ourpublisherpartnerforOCRGCSETwentyFirstCenturyScience,tohelpensuretheirnewresourcesareavailablewhenyouneedthemandmatchthenewspecifications.
OxfordUniversityPressisworkingwithourscienceteam,theNuffieldFoundationandUniversityofYorkScienceEducationGrouptopublishneweditionsofthepopularTwentyFirstCenturyScienceresources.Theseresourcesarelively,engagingandmakesciencerelevanttoeverystudent.
Thesecondeditionoftheseresourcesispackedwithuptodatescience,aswellasthefamiliartopicsyouenjoyteachingincludingstepbystepguidanceforansweringalltypesofexamquestions,extendedresponsequestionsandsupportforthenewcontrolledassessment.
ToorderanEvaluationPack,orforfurtherdetails,pleasevisittheOxfordUniversityPresswebsiteatwww.oxfordsecondary.co.uk/twentyfirstcenturyscience.
OtherendorsedresourcesavailableforthisspecificationincludeOCRGCSETwentyFirstCenturySciencefromCollins.
CollinsisworkingwithateamofexperiencedauthorstoprovideresourceswhichwillhelpyoudeliverthenewOCRGCSETwentyFirstCenturySciencespecifications.TheScience,AdditionalScienceandSeparateSciencecomponentsbuildoneachothersoyourdepartmentcanbuyasneededandusethemwithallstudentstakingdifferentGCSEscienceroutes.
Reduceplanningtime–thestudentbooks,teacherpacks,homeworkactivities,interactivebooksandassessmentpackagearefullyintegratedandmatchedtotheCollinsGCSETwentyFirstCenturyScienceschemeofworksoyoucangetstartedstraightaway.
ForfurtherdetailsandtoorderanEvaluationPackvisitwww.collinseducation.com/gcsescience2011.
6.2.2 Endorsed publishers
6.2.1 Publisher partner
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OCRwillofferarangeofsupportactivitiesforallpractitionersthroughoutthelifetimeofthequalificationtoensuretheyhavetherelevantknowledgeandskillstodeliverthequalification.
PleaseseeEventBookerforfurtherinformation.
6.3 Training
6.4 OCR support services
6.4.1 Active Results
ActiveResultsisavailabletoallcentresofferingtheOCRGCSEAdditionalScienceAspecification.
ActiveResultsisafreeresultsanalysisservicetohelpteachersreviewtheperformanceofindividualcandidatesorwholeschools.
Datacanbeanalysedusingfiltersonseveralcategoriessuchasgenderandotherdemographicinformation,aswellasprovidingbreakdownsofresultsbyquestionandtopic.
ActiveResultsallowsyoutolookingreaterdetailatyourresultsinanumberofways:
• richerandmoregranulardatawillbemadeavailabletocentres,includingquestion-leveldataavailablefrome-marking
• youcanidentifythestrengthsandweaknessesofindividualcandidatesandyourcentre’scohortasawhole
• oursystemshavebeendevelopedincloseconsultationwithteacherssothatthetechnologydeliverswhatyouneed.
FurtherinformationonActiveResultscanbefoundontheOCRwebsite.
OCRInterchangehasbeendevelopedtohelpyoutocarryoutday-to-dayadministrationfunctionsonline,quicklyandeasily.Thesiteallowsyoutoregisterandentercandidatesonline.Inaddition,youcangainimmediateandfreeaccesstocandidateinformationatyourconvenience.SignupontheOCRwebsite.
6.4.2 OCR Interchange
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Equality and inclusion in GCSE Additional Science A
7.1 Equality Act information relating to GCSE Additional Science A
GCSEsoftenrequireassessmentofabroadrangeofcompetences.Thisisbecausetheyaregeneralqualificationsand,assuch,preparecandidatesforawiderangeofoccupationsandhigherlevelcourses.
TherevisedGCSEqualificationandsubjectcriteriawerereviewedbytheregulatorsinordertoidentifywhetheranyofthecompetencesrequiredbythesubjectpresentedapotentialbarriertoanydisabledcandidates.Ifthiswasthecase,thesituationwasreviewedagaintoensurethatsuchcompetenceswereincludedonlywhereessentialtothesubject.Thefindingsofthisprocesswerediscussedwithdisabilitygroupsandwithdisabledpeople.
Reasonableadjustmentsaremadefordisabledcandidatesinordertoenablethemtoaccesstheassessmentsandtodemonstratewhattheyknowandcando.Forthisreason,veryfewcandidateswillhaveacompletebarriertotheassessment.InformationonreasonableadjustmentsisfoundinAccess Arrangements, Reasonable Adjustments and Special ConsiderationbytheJointCouncilwww.jcq.org.uk.
Candidateswhoareunabletoaccesspartoftheassessment,evenafterexploringallpossibilitiesthroughreasonableadjustments,maystillbeabletoreceiveanawardbasedonthepartsoftheassessmenttheyhavetaken.
TheaccessarrangementspermissibleforuseinthisspecificationareinlinewithOfqual’sGCSEsubjectcriteriaequalitiesreviewandareasfollows:
Yes/No Type of Assessment
Readers Yes Allassessments
Scribes Yes Allassessments
Practicalassistants Yes Allcontrolledassessments.Thepracticalassistantmayassistwithassessedpracticalexperimentsunderinstructionfromthecandidate.
Wordprocessors Yes Allassessments
Transcripts Yes Allassessments
Orallanguagemodifiers Yes Allassessments
BSLsigners Yes Allassessments
Modifiedquestionpapers Yes Allassessments
Extratime Yes Allassessments
7
101 ©OCR2012GCSEAdditionalScienceA
7
Allcandidateswithademonstrableneedmaybeeligibleforaccessarrangementstoenablethemtoshowwhattheyknowandcando.ThecriteriaforeligibilityforaccessarrangementscanbefoundintheJCQdocumentAccess Arrangements, Reasonable Adjustments and Special Consideration.
Candidateswhohavebeenfullypreparedfortheassessmentbutwhohavebeenaffectedbyadversecircumstancesbeyondtheircontrolatthetimeoftheexaminationmaybeeligibleforspecialconsideration.Asabove,centresshouldconsulttheJCQdocumentAccess Arrangements, Reasonable Adjustments and Special Consideration.
7.2 Arrangements for candidates with particular requirements (including Special Consideration)
102 ©OCR2012GCSEAdditionalScienceA
8 Administration of GCSE Additional Science A
InDecember2011theGCSEqualificationcriteriawerechangedbyOfqual.Asaresult,allGCSEqualificationshavebeenupdatedtocomplywiththenewregulations.
ThemostsignificantchangeforallGCSEqualificationsisthat,from2014,unitisedspecificationsmustrequirethat100%oftheassessmentisterminal.
Pleasenotethattherearenochangestotheterminalruleandre-sitrulesfortheJanuary2013andJune2013examinationseries:
• atleast40%oftheassessmentmustbetakenintheexaminationseriesinwhichthequalificationiscertificated
• candidatesmayre-siteachunitoncebeforecertification,i.e.eachcandidatecanhavetwoattemptsataunitbeforecertification.
ForfullinformationontheassessmentavailabilityandrulesthatapplyintheJanuary2013andJune2013examinationseries,pleaserefertothepreviousversionofthisspecificationGCSEAdditionalScienceA(March2011)availableonthewebsite.
ThesectionsbelowexplaininmoredetailtherulesthatapplyfromtheJune2014examinationseriesonwards.
ThereisoneexaminationseriesavailableeachyearinJune(allunitsareavailableeachyearinJune).
GCSEAdditionalScienceAcertificationisavailableinJune2014andeachJunethereafter.
Unit A162 Unit A172 Unit A182 Unit A154 Certification availability
June 2014 3 3 3 3 3
June 2015 3 3 3 3 3
ForGCSEAdditionalScienceA,fromJune2014onwards,a100%terminalruleapplies.Candidatesmustenterforalltheirunitsintheseriesinwhichthequalificationiscertificated.
Candidatesmayenterforthequalificationanunlimitednumberoftimes.
Whereacandidatere-takesaqualification,allunitsmustbere-enteredandallexternallyassessedunitsmustbere-takeninthesameseriesasthequalificationisre-certificated.Thenewresultsfortheseunitswillbeusedtocalculatethenewqualificationgrade.Anyresultspreviouslyachievedcannotbere-used.
Forthecontrolledassessmentunit,candidateswhoarere-takingaqualificationcanchooseeithertore-takethatcontrolledassessmentunitortocarryforwardtheresultforthatunitthatwasusedtowardsthepreviouscertificationofthesamequalification.
• Whereacandidatedecidestore-takethecontrolledassessment,thenewresultwillbetheoneusedtocalculatethenewqualificationgrade.Anyresultspreviouslyachievedcannotbere-used.
8.1 Availability of assessment from 2014
8.2 Certification rules
8.3 Rules for re-taking a qualification
103 ©OCR2012GCSEAdditionalScienceA
8
• Whereacandidatedecidestocarryforwardaresultforcontrolledassessment,theymustbeenteredforthecontrolledassessmentunitinthere-takeseriesusingtheentrycodeforthecarryforwardoption(seesection8.4).
CentresmustbeapprovedtoofferOCRqualificationsbeforetheycanmakeanyentries,includingestimatedentries.ItisrecommendedthatcentresapplytoOCRtobecomeanapprovedcentrewellinadvanceofmakingtheirfirstentries.CentresmusthavemadeanentryforaunitinorderforOCRtosupplytheappropriateformsandadministrativematerials.
It is essentialthatcorrectunitentrycodesareusedwhenmakingunitentries.
FortheexternallyassessedunitsA162,A172andA182candidatesmustbeenteredforeithercomponent01(FoundationTier)or02(HigherTier)usingtheappropriateunitentrycodefromthetablebelow.Itisnotpossibleforacandidatetotakebothcomponentsforaparticularunitwithinthesameseries;however,differentunitsmaybetakenatdifferenttiers.
Forthecontrolledassessmentunit,centrescandecidewhethertheywanttosubmitcandidates’workformoderationthroughtheOCRRepositoryorbypost.Candidatessubmittingcontrolledassessmentmustbeenteredfortheappropriateunitentrycodefromthetablebelow.Candidateswhoarere-takingthequalificationandwhowanttocarryforwardthecontrolledassessmentshouldbeenteredusingtheunitentrycodeforthecarryforwardoption.
Centresshouldnotethatcontrolledassessmenttaskscanstillbecompletedatatimewhichisappropriatetothecentre/candidate.However,wheretaskschangefromyeartoyear,centreswouldhavetoensurethatcandidateshadcompletedthecorrecttask(s)fortheyearofentry.
Unit entry code
Component code
Assessment method
Unit titles
A162F 01 WrittenPaper UnitA162: Biology A Modules B4, B5 and B6 (FoundationTier)
A162H 02 WrittenPaper UnitA162:Biology A Modules B4, B5 and B6(HigherTier)
A172F 01 WrittenPaper UnitA172:Chemistry A Modules C4, C5 and C6(FoundationTier)
A172H 02 WrittenPaper UnitA172:Chemistry A Modules C4, C5 and C6(HigherTier)
A182F 01 WrittenPaper UnitA182:Physics A Modules P4, P5 and P6(FoundationTier)
A182H 02 WrittenPaper UnitA182:Physics A Modules P4, P5 and P6(HigherTier)
A154A 01 ModeratedviaOCRRepository
UnitA154:Additional Science A Controlled assessment
A154B 02 Moderatedviapostalmoderation
UnitA154:Additional Science A Controlled assessment
A154C 80 Carriedforward UnitA154:Additional Science A Controlled assessment
8.4 Making entries
8.4.1 Making unit entries
104 ©OCR2012GCSEAdditionalScienceA
8
Candidatesmustbeenteredforqualificationcertificationseparatelyfromunitassessment(s).Ifacertificationentryisnotmade,nooverallgradecanbeawarded.
Centresmustentercandidatesfor:
• GCSEAdditionalScienceAcertificationcodeJ242.
Undercertaincircumstances,acentremaywishtoquerytheresultissuedtooneormorecandidates.EnquiriesaboutresultsforGCSEunitsmustbemadeimmediatelyfollowingtheseriesinwhichtherelevantunitwastakenandbytherelevantenquiriesaboutresultsdeadlineforthatseries.
PleaserefertotheJCQPost-Results ServicesbookletandtheOCRAdmin Guide: 14–19 Qualifications forfurtherguidanceonEnquiriesaboutresultsanddeadlines.CopiesofthelatestversionsofthesedocumentscanbeobtainedfromtheOCRwebsiteatwww.ocr.org.uk.
Everyspecificationisassignedanationalclassificationcodeindicatingthesubjectareatowhichitbelongs.Theclassificationcodeforthisspecificationis1320.
CentresshouldbeawarethatcandidateswhoenterformorethanoneGCSEqualificationwiththesameclassificationcodewillhaveonlyonegrade(thehighest)countedforthepurposeoftheSchoolandCollegePerformanceTables.
Centresmaywishtoadvisecandidatesthat,iftheytaketwospecificationswiththesameclassificationcode,collegesareverylikelytotaketheviewthattheyhaveachievedonlyoneofthetwoGCSEs.ThesameviewmaybetakenifcandidatestaketwoGCSEspecificationsthathavedifferentclassificationcodesbuthavesignificantoverlapofcontent.Candidateswhohaveanydoubtsabouttheirsubjectcombinationsshouldseekadvice,eitherfromtheircentreorfromtheinstitutiontowhichtheywishtoprogress.
8.4.2 Certification entries
8.5 Enquiries about results
8.6 Prohibited qualifications and classification code
105 ©OCR2012GCSEAdditionalScienceA
9Other information about GCSE Additional Science A
ThisspecificationhasbeendevelopedalongsideGCSEScienceA,GCSEBiologyA,GCSEChemistryA,GCSEPhysicsAandGCSEAdditionalAppliedScience.
ThisspecificationincludesthecontentofModules4–6ofGCSEBiologyA,GCSEChemistryAandGCSEPhysicsA.
AspectsofthecontrolledassessmentofskillsarecommonacrossGCSEAdditionalScienceA,GCSEBiologyA,GCSEChemistryAandGCSEPhysicsA.
GCSEqualificationsaregeneralqualificationswhichenablecandidatestoprogresseitherdirectlytoemployment,ortoproceedtofurtherqualifications.
ProgressiontofurtherstudyfromGCSEwilldependuponthenumberandnatureofthegradesachieved.Broadly,candidateswhoareawardedmainlyGradesDtoGatGCSEcouldeitherstrengthentheirbasethroughfurtherstudyofqualificationsatLevel1withintheNationalQualificationsFrameworkorcouldproceedtoLevel2.CandidateswhoareawardedmainlyGradesA*toCatGCSEwouldbewellpreparedforstudyatLevel3withintheNationalQualificationsFramework.
OCRhastakengreatcareinpreparationofthisspecificationandassessmentmaterialstoavoidbiasofanykind.Specialfocusisgiventothe9strandsoftheEqualityActwiththeaimofensuringbothdirectandindirectdiscriminationisavoided.
Thisspecificationcompliesinallrespectswiththecurrent:General Conditions of Recognition; GCSE, GCE, Principal Learning and Project Code of Practice; GCSE Controlled Assessment regulationsandtheGCSE subject criteria for Science. AlldocumentsareavailableontheOfqualwebsite.
ThisspecificationandassociatedassessmentmaterialsareinEnglishonly.OnlyanswerswritteninEnglishwillbeassessed.
9.1 Overlap with other qualifications
9.2 Progression from this qualification
9.3 Avoidance of bias
9.4 Regulatory requirements
9.5 Language
106 ©OCR2012GCSEAdditionalScienceA
9
Thisspecificationoffersopportunitieswhichcancontributetoanunderstandingoftheseissuesinthefollowingtopics.
Thetablebelowgivessomeexampleswhichcouldbeusedwhenteachingthecourse.
Issue Opportunities for teaching the issues during the course
Spiritual issuesScientificexplanationswhichgiveinsightintohumannature.
B6:Insightintotheabilityofhumanbeingstosurviveunderextremeconditions.B6:Thestudyofhigherfunctionsofthehumanbrain–intelligence,memory,languageandconsciousness.
Moral issuesThecommitmentofscientiststopublishtheirfindingsandsubjecttheirideastotestingbyothers.
PracticalInvestigation:reviewingthestrategyandprocedures.
Social issuesScientificexplanationswhichgiveinsightintoeverydayexperiences.
P4:Theoriesofforcesandmotionandtheirimplicationsforhumansafetyinmotorvehiclesandotherformsoftransport.P5:Modelsforthebehaviourofelectriccircuitsandtheirpracticalimportanceforthegenerationofelectricity.
Economic issuesTherangeoffactorswhichhavetobeconsideredwhenweighingthecostsandbenefitsofscientificactivity.
C6:Evaluatingthecostsandbenefitsassociatedwithchemicalmanufacturing.
Cultural issuesScientificexplanationswhichgiveinsightintothelocalandglobalenvironment.
C5:Insightintothechemicalnatureofnaturalchangesinthelithosphere,hydrosphere,atmosphereandbiosphere.
9.6 Spiritual, moral, ethical, social, legislative, economic and cultural issues
9.7 Sustainable development, health and safety considerations and European developments, consistent with international agreements
Thisspecificationsupportstheseissues,consistentwithcurrentEUagreements,asoutlinedbelow.
Thespecificationincorporatesspecificmodulesonhealthandwelfareandontheenvironmentwithinitscontent.Thesemodulesencouragecandidatestodevelopenvironmentalresponsibilitybaseduponasoundunderstandingoftheprincipleofsustainabledevelopment.
107 ©OCR2012GCSEAdditionalScienceA
9
ThisspecificationprovidesopportunitiesforthedevelopmentoftheKeySkillsofCommunication, Application of Number, Information and Communication Technology, Working with Others, Improving Own Learning and Performance and Problem SolvingatLevels1and/or2.However,theextenttowhichthisevidencefulfilstheKeySkillscriteriaattheselevelswillbetotallydependentonthestyleofteachingandlearningadoptedforeachunit.
ThefollowingtableindicateswhereopportunitiesmayexistforatleastsomecoverageofthevariousKeySkillscriteriaatLevels1and/or2foreachunit.
UnitC AoN ICT WwO IOLP PS
1 2 1 2 1 2 1 2 1 2 1 2
A162 3 3 3 3 3 3 3 3 3 3 3 3
A172 3 3 3 3 3 3 3 3 3 3 3 3
A182 3 3 3 3 3 3 3 3 3 3 3 3
A154 3 3 3 3 3 3 3 3 3 3 3 3
9.8 Key Skills
9.9 ICT
Inordertoplayafullpartinmodernsociety,candidatesneedtobeconfidentandeffectiveusersofICT.ThisspecificationprovidescandidateswithawiderangeofappropriateopportunitiestouseICTinordertofurthertheirstudyofscience.
OpportunitiesforICTinclude:
• usingvideosclipstoprovidethecontextfortopicsstudiedandtoillustratethepracticalimportanceofthescientificideas
• gatheringinformationfromtheinternetandsoftwarelibraries
• gatheringdatausingsensorslinkedtodata-loggersordirectlytocomputers
• usingspreadsheetsandothersoftwaretoprocessdata
• usinganimationsandsimulationstovisualisescientificideas
• usingmodellingsoftwaretoexploretheories
• usingsoftwaretopresentideasandinformationonpaperandonscreen.
ParticularopportunitiesfortheuseofICTappearintheintroductionstoeachofthemodules.
9.10 Citizenship
FromSeptember2002,theNationalCurriculumforEnglandatKeyStage4includesamandatoryprogrammeofstudyforCitizenship.
GCSEAdditionalScienceAisdesignedasascienceeducationforfuturecitizenswhichnotonlycoversaspectsoftheCitizenshipprogrammeofstudybutalsoextendsbeyondthatprogrammebydealingwithimportantaspectsofsciencewhichallpeopleencounterintheireverydaylives.
108 ©OCR2012GCSEAdditionalScienceA
Appendix A: Guidance for the production of electronic controlled assessment
Structure for evidence
Data formats for evidence
Acontrolledassessmentportfolioisacollectionoffoldersandfilescontainingthecandidate’sevidence.Foldersshouldbeorganisedinastructuredwaysothattheevidencecanbeaccessedeasilybyateacherormoderator.Thisstructureiscommonlyknownasafoldertree.Itwouldbehelpfulifthelocationofparticularevidenceismadeclearbynamingeachfileandfolderappropriatelyandbyuseofanindexcalled‘HomePage’.
Thereshouldbeatoplevelfolderdetailingthecandidate’scentrenumber,candidatenumber,surnameandforename,togetherwiththeunitcodeA154,sothattheportfolioisclearlyidentifiedastheworkofonecandidate.
Eachcandidateproducesanassignmentforcontrolledassessment.Theevidenceshouldbecontainedwithinaseparatefolderwithintheportfolio.Thisfoldermaycontainseparatefiles.
Eachcandidate’scontrolledassessmentportfolioshouldbestoredinasecureareaonthecentre’snetwork.PriortosubmittingthecontrolledassessmentportfoliotoOCR,thecentreshouldaddafoldertothefoldertreecontainingcontrolledassessmentandsummaryforms.
Inordertominimisesoftwareandhardwarecompatibilityissuesitwillbenecessarytosavecandidates’workusinganappropriatefileformat.
Candidatesmustuseformatsappropriatetotheevidencethattheyareprovidingandappropriatetoviewingforassessmentandmoderation.Openfileformatsorproprietaryformatsforwhichadownloadablereaderorplayerisavailableareacceptable.Wherethisisnotavailable,thefileformatisnotacceptable.
Electroniccontrolledassessmentisdesignedtogivecandidatesanopportunitytodemonstratewhattheyknow,understandandcandousingcurrenttechnology.Candidatesdonotgainmarksforusingmoresophisticatedformatsorforusingarangeofformats.Acandidatewhochoosestouseonlyworddocumentswillnotbedisadvantagedbythatchoice.
Evidencesubmittedislikelytobeintheformofwordprocesseddocuments,PowerPointpresentations,digitalphotosanddigitalvideo.
Toensurecompatibility,allfilessubmittedmustbeintheformatslistedbelow.Wherenewformatsbecomeavailablethatmightbeacceptable,OCRwillprovidefurtherguidance.OCRadvisesagainstchangingthefileformatthatthedocumentwasoriginallycreatedin.Itisthecentre’sresponsibilitytoensurethattheelectronicportfoliossubmittedformoderationareaccessibletothemoderatorandfullyrepresenttheevidenceavailableforeachcandidate.
A
109 ©OCR2012GCSEAdditionalScienceA
AAccepted file formats
Movie formats for digital video evidence
MPEG(*.mpg)
QuickTimemovie(*.mov)
MacromediaShockwave(*.aam)
MacromediaShockwave(*.dcr)
Flash(*.swf)
WindowsMediaFile(*.wmf)
MPEGVideoLayer4(*.mp4)
Audio or sound formats
MPEGAudioLayer3(*.mp3)
Graphics formats including photographic evidence
JPEG(*.jpg)
Graphicsfile(*.pcx)
MSbitmap(*.bmp)
GIFimages(*.gif)
Animation formats
MacromediaFlash(*.fla)
Structured markup formats
XML(*.xml)
Text formats
CommaSeparatedValues(.csv)
PDF(.pdf)
Richtextformat(.rtf)
Textdocument(.txt)
Microsoft Office suite
PowerPoint(.ppt)
Word(.doc)
Excel(.xls)
Visio(.vsd)
Project(.mpp)
110 ©OCR2012GCSEAdditionalScienceA
Appendix B: Mathematics skills for GCSE science qualifications
Candidatesarepermittedtousecalculatorsinallassessments.
Candidatesshouldbeableto:
1 understandnumber,sizeandscaleandthequantitativerelationshipbetweenunits
2 understandwhenandhowtouseestimation
3 carryoutcalculationsinvolving+,-,×,÷,eithersinglyorincombination,decimals,fractions,percentagesandpositivewholenumberpowers
4 provideanswerstocalculationstoanappropriatenumberofsignificantfigures
5 understandandusethesymbols=,<,>,~
6 understandandusedirectproportionandsimpleratios
7 calculatearithmeticmeans
8 understandandusecommonmeasuresandsimplecompoundmeasuressuchasspeed
9 plotanddrawgraphs(linegraphs,barcharts,piecharts,scattergraphs,histograms)selectingappropriatescalesfortheaxes
10 substitutenumericalvaluesintosimpleformulaeandequationsusingappropriateunits
11 translateinformationbetweengraphicalandnumericform
12 extractandinterpretinformationfromcharts,graphsandtables
13 understandtheideaofprobability
14 calculatearea,perimetersandvolumesofsimpleshapes.
In addition, Higher Tier candidates should be able to:
15 interpret, order and calculate with numbers written in standard form
16 carry out calculations involving negative powers (only –1 for rate)
17 change the subject of an equation
18 understand and use inverse proportion
19 understand and use percentiles and deciles.
B
111 ©OCR2012GCSEAdditionalScienceA
Appendix C: Physical quantities and units C
ItisexpectedthatcandidateswillshowanunderstandingofthephysicalquantitiesandcorrespondingSIunitslistedbelowandwillbeabletousetheminquantitativeworkandcalculations.Whenevertheyarerequiredforsuchquestions,unitswillbeprovidedand,wherenecessary,explained.
Fundamental physical quantities
Physicalquantity Unit(s)
length metre(m);kilometre(km);centimetre(cm);millimetre(mm);nanometre(nm)
mass kilogram(kg);gram(g);milligram(mg)
time second(s);millisecond(ms);year(a);millionyears(Ma);billionyears(Ga)
temperature degreeCelsius(°C);kelvin(K)
current ampere(A);milliampere(mA)
Derived physical quantities and units
Physicalquantity Unit(s)
area cm2;m2
volume cm3;dm3;m3;litre(l );millilitre(ml)
density kg/m3;g/cm3
speed,velocity m/s;km/h
acceleration m/s2
momentum kgm/s
force newton(N)
pressure N/m2;pascal(Pa)
gravitationalfieldstrength
N/kg
energy joule(J);kilojoule(kJ);megajoule(MJ);kilowatthour(kWh);megawatthour(MWh)
power watt(W);kilowatt(kW);megawatt(MW)
frequency hertz(Hz);kilohertz(kHz)
information bytes(B);kilobytes(kB);megabytes(MB)
potentialdifference volt(V)
resistance ohm(Ω)
radiationdose sievert(Sv)
distance(inastronomy)
light-year(ly);parsec(pc)
powerofalens dioptre(D)
112 ©OCR2012GCSEAdditionalScienceA
C
Prefixes for units
nano (n) onethousandmillionth 0.000000001 ×10–9
micro (µ) onemillionth 0.000001 ×10–6
milli (m) onethousandth 0.001 ×10–3
kilo (k) ×onethousand 1000 ×103
mega (M) ×onemillion 1000000 ×106
giga (G) ×onethousandmillion 1000000000 ×109
tera (T) ×onemillionmillion 1000000000000 ×1012
113 ©OCR2012GCSEAdditionalScienceA
DAppendix D: Health and safety
InUKlaw,healthandsafetyistheresponsibilityoftheemployer.FormostestablishmentsenteringcandidatesforGCSE,thisislikelytobethelocaleducationauthorityorthegoverningbody.Employees,i.e.teachersandlecturers,haveadutytocooperatewiththeiremployeronhealthandsafetymatters.Variousregulations,butespeciallytheCOSHHRegulations2002andtheManagementofHealthandSafetyatWorkRegulations1999,requirethatbeforeanyactivityinvolvingahazardousprocedureorharmfulmicroorganismsiscarriedout,orhazardouschemicalsareusedormade,theemployermustprovideariskassessment.Formembers,theCLEAPSS®guide,Managing Risk Assessment in Science*offersdetailedadvice.MosteducationemployershaveadoptedarangeofnationallyavailablepublicationsasthebasisfortheirModelRiskAssessments.Thosecommonlyusedinclude:
Safety in Science Education,DfEE,1996,HMSO,ISBN011270915X;
Topics in Safety,3rdedition,2001,ASEISBN0863573169;
Safeguards in the School Laboratory,11thedition,2006,ASEISBN9780863574085;
CLEAPSS®Hazcards,2007editionandlaterupdates*;
CLEAPSS®Laboratory Handbook*;
Hazardous Chemicals,AManualforScienceEducation,1997,SSERCLimited,ISBN0953177602.
Whereanemployerhasadoptedtheseorotherpublicationsasthebasisoftheirmodelriskassessments,anindividualschoolorcollegethenhastoreviewthem,toseeifthereisaneedtomodifyoradapttheminsomewaytosuittheparticularconditionsoftheestablishment.Suchadaptationsmightincludeareducedscaleofworking,decidingthatthefumecupboardprovisionwasinadequateortheskillsofthecandidateswereinsufficienttoattemptparticularactivitiessafely.Thesignificantfindingsofsuchriskassessmentshouldthenberecorded,forexampleonschemesofwork,publishedteachersguides,worksheets,etc.Thereisnospecificlegalrequirementthatdetailedriskassessmentformsshouldbecompleted,althoughafewemployersrequirethis.Whereprojectworkorindividualinvestigations,sometimeslinkedtowork-relatedactivities,areincludedinspecificationsthismaywellleadtotheuseofnovelprocedures,chemicalsormicro-organisms,whicharenotcoveredbytheemployer’smodelriskassessments.Theemployershouldhavegivenguidanceonhowtoproceedinsuchcases.Often,formembers,itwillinvolvecontactingCLEAPSS®(or,inScotland,SSERC).*These,andotherCLEAPSS®publications,areontheCLEAPSS®SciencePublicationsCD-ROMissuedannuallytomembers.NotethatCLEAPSS®publicationsareonlyavailabletomembers.FormoreinformationaboutCLEAPSS®gotowww.cleapss.org.uk.InScotland,SSERC(www.sserc.org.uk)hasasimilarroletoCLEAPSS®andtherearesomereciprocalarrangements.
114 ©OCR2012GCSEAdditionalScienceA
E Appendix E: Electrical symbols
G
M
A
V
junction ofconductors
ammeter
switch switch
primary orsecondary cell
motor
battery of cells or fixed resistor
variable resistor
power supply
lamp thermistor
©OCR2012GCSEAdditionalScienceA
115
App
endi
x F:
Per
iodi
c ta
ble
FTh
e Pe
riod
ic T
able
of
the
Elem
ents
* T
he la
ntha
noid
s (a
tom
ic n
umbe
rs 5
8-71
) an
d th
e ac
tino
ids
(ato
mic
num
bers
90-
103)
hav
e be
en o
mit
ted.
The
rela
tive
ato
mic
mas
ses
of c
oppe
r an
d ch
lori
ne h
ave
not
been
rou
nded
to
the
near
est
who
le n
umbe
r.
12
34
56
70
Key
1 Hhy
drog
en
1
4 He
heliu
m
2
7 Lilit
hium 3
9 Bebe
rylli
um
4
rela
tive
ato
mic
mas
sat
omic
sym
bol
nam
e
atom
ic (
prot
on)
num
ber
11 Bbo
ron
5
12 Cca
rbon 6
14 Nni
trog
en
7
16 Oox
ygen 8
19 Ffl
uori
ne
9
20 Ne
neon 10
23 Na
sodi
um
11
24 Mg
mag
nesi
um
12
27 Al
alum
iniu
m
13
28 Sisi
licon
14
31 Pph
osph
orus
15
32 Ssu
lfur
16
35.5 Cl
chlo
rine
17
40 Ar
argo
n
18
39 Kpo
tass
ium
19
40 Caca
lciu
m
20
45 Scsc
andi
um
21
48 Titi
tani
um
22
51 Vva
nadi
um
23
52 Crch
rom
ium
24
55 Mn
man
gane
se
25
56 Fe iron 26
59 Co coba
lt
27
59 Ni
nick
el
28
63.5
Cu copp
er
29
65 Zn zinc 30
70 Ga
galli
um
31
73 Ge
germ
aniu
m
32
75 As
arse
nic
33
79 Sese
leni
um
34
80 Brbr
omin
e
35
84 Krkr
ypto
n
36
85 Rbru
bidi
um
37
88 Srst
ront
ium
38
89 Yyt
triu
m
39
91 Zrzi
rcon
ium
40
93 Nb
niob
ium
41
96 Mo
mol
ybde
num
42
[98] Tc
tech
neti
um
43
101
Ruru
then
ium
44
103
Rhrh
odiu
m
45
106
Pdpa
lladi
um
46
108
Ag
silv
er
47
112
Cdca
dmiu
m
48
115
Inin
dium
49
119
Sn tin 50
122
Sban
tim
ony
51
128
Tete
lluri
um
52
127 I
iodi
ne
53
131
Xe xeno
n
54
133
Csca
esiu
m
55
137
Baba
rium
56
139
La*
lant
hanu
m
57
178
Hf
hafn
ium
72
181
Tata
ntal
um
73
184
Wtu
ngst
en
74
186
Rerh
eniu
m
75
190
Os
osm
ium
76
192
Irir
idiu
m
77
195
Ptpl
atin
um
78
197
Au
gold 79
201
Hg
mer
cury
80
204
Tlth
alliu
m
81
207
Pb lead 82
209
Bibi
smut
h
83
[209
]Po
polo
nium
84
[210
]A
tas
tati
ne
85
[222
]Rn rado
n
86
[223
]Fr
fran
cium
87
[226
]Ra
radi
um
88
[227
]A
c*ac
tini
um
89
[261
]Rf
ruth
erfo
rdiu
m
104
[262
]D
bdu
bniu
m
105
[266
]Sg
seab
orgi
um
106
[264
]Bh
bohr
ium
107
[277
]H
sha
ssiu
m
108
[268
]M
tm
eitn
eriu
m
109
[271
]D
sda
rmst
adti
um
110
[272
]Rg
roen
tgen
ium
111
Elem
ents
wit
h at
omic
num
bers
112
-116
hav
e be
en r
epor
ted
but
not
fully
auth
enti
cate
d
116 ©OCR2012GCSEAdditionalScienceA
G Appendix G: Qualitative analysis
Tests for ions with a negative charge
Tests for ions with a positive charge
ion test observation
carbonateCO3
2–adddiluteacid thesolutioneffervesces;carbon
dioxidegasisproduced(thegasturnslimewaterfromcolourlesstomilky)
chlorideCl–
adddilutenitricacid,thenaddsilvernitrate
awhiteprecipitateforms
bromideBr–
adddilutenitricacid,thenaddsilvernitrate
acreamprecipitateforms
iodideI–
adddilutenitricacid,thenaddsilvernitrate
ayellowprecipitateforms
sulfateSO4
2–adddiluteacid,thenaddbariumchlorideorbariumnitrate
awhiteprecipitateforms
ion test observation
calciumCa2+
adddilutesodiumhydroxide awhiteprecipitateforms;theprecipitatedoesnotdissolveinexcesssodiumhydroxide
copperCu2+
adddilutesodiumhydroxide alightblueprecipitateforms;theprecipitatedoesnotdissolveinexcesssodiumhydroxide
iron(II)Fe2+
adddilutesodiumhydroxide agreenprecipitateforms;theprecipitatedoesnotdissolveinexcesssodiumhydroxide
iron(III)Fe3+
adddilutesodiumhydroxide ared-brownprecipitateforms;theprecipitatedoesnotdissolveinexcesssodiumhydroxide
zincZn2+
adddilutesodiumhydroxide awhiteprecipitateforms;theprecipitatedissolvesinexcesssodiumhydroxide
117 ©OCR2012GCSEAdditionalScienceA
Appendix H: Hazard labelling H
SpecificationstatementsC4.1.18andC6.1.6requirecandidatestorecallthechemicalhazardsymbolsassociatedwithchemicalsthatcanbeexplosive,toxic,corrosive,oxidizingandhighlyflammable.
Teachersandtechnicianswillbefamiliarwiththesquaresymbolswithorangebackgrounds,asdefinedinEECDirective67/548/EEC.However,thisDirectivewillberepealedon1June2015andthesymbolswillnolongerbeusedafterthatdate.
Anewsetofdiamond-shapedhazardsymbolswithwhitebackgroundsisbeingintroducedinEurope,inaccordancewiththeUnited Nations Globally Harmonized System of Classification and Labelling of Chemicals (the“GHS”).TheGHShasbeenadoptedinEuropeundertheRegulation on the Classification, Labelling and Packaging of Substances and Mixtures(the“CLP”).
Theperiodupto1June2015isconsideredtobeatransitionalperiodinwhichbothsystemsoflabellingwillbeinuse.Hence,studentsarelikelytoseebothsetsofsymbolsonchemicalbottlesandchemicalsafetydatasheetsduringthelifetimeofthisspecification.
UnderthenewGHS/CLPsystem,suppliersarerequiredtolabelchemicalswithanappropriatesymbol,signalword,hazardstatement(s)andprecautionarystatement(s).
GuidanceforteachersandtechnicianshavebeenissuedbyCLEAPSSintheleaflet‘An introduction to GHS / CLP chemical hazard labelling’,availablefreeat:
www.cleapss.org.uk/attachments/article/0/GL%20101%20GHS%20CLP%20labelling.pdf?Secondary/Science/Guidance%20Leaflets/
UnderthenewGHS/CLPsystem,thefamiliar‘X’symbolassociatedwithchemicalsthatcanbeharmfulorirritantwillnolongerbeused.Thesechemicalswillbelabelledwithothersymbolsappropriatetothenatureofthehazard,alongwithappropriatesignalword,hazardstatement(s)andprecautionarystatement(s).
Studentsshouldbefamiliarwithbothsystemsofhazardlabelling,andshouldbeabletorecogniseduringassessmentthesymbolsusedunderbothsystems(limitedtoexplosive,toxic,corrosive,oxidizingandhighlyflammablehazards),asshownbelow.
How does this affect teaching and assessment?
Hazard symbols under EEC Directive 67/548/EEC
Hazard symbols under the GHS / CLP system
Explosive Toxic Corrosive Oxidizing Highly flammable
118 ©OCR2012GCSEAdditionalScienceA
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