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OASB Science Department
Chemistry Paper 2 Revision Pack Double Foundation Contents LessonMastery Matrix Chemistry Paper 2Knowledge 1Rates of reaction & reversible reactions Summary PageNotes pageExam QuestionsKnowledge 2Gas tests and Chromatography Summary PageNotes pageExam QuestionsKnowledge 3The Earth’s Early Atmosphere & Global warming Summary PageNotes pageExam QuestionsKnowledge 4Air Pollution & Finite resources Summary PageNotes pageExam QuestionsKnowledge 5Water and waste & Life Cycle Assessments Summary PageNotes pageExam Questions
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Topic Tier Revision Guide (combined) Learning statement
Mixtures F Define ‘pure substances’ and explain the difference between its scientific and everyday meaningMixtures F Use melting and boiling point data to establish pure substances from mixtures
Mixtures F Describe what a ‘formulation’ is and give examples (Fuels, cleaning agents, paints, medicines, alloys, fertilisers and foods)
Mixtures F Describe the two phases (stationary and mobile) of chromatography and its purposeMixtures F Calculate Rf valuesMixtures F Interpret chromatograms to decide whether a substance is pure of a mixture
Mixtures F RP Chromatography: Use paper chromatography to investigate the colours within different substances and calculate Rf values
Mixtures F Explain the difference in difficulty of separating compounds compared to mixturesMetals in the periodic
table F Explain what an alloy is and how it’s properties differ from a pure metal
Groups in the periodic table F Describe the gas test for carbon dioxide, hydrogen, oxygen and chlorine
Rates of reaction F 124 Calculate the mean rate of reaction Rates of reaction F 124 Recall the units for mass (g), volume (cm3) and rate (g/s, cm3/s, mol/s)Rates of reaction F 125 Draw tangents on curves in order to calculate rates of reactionRates of reaction F 124-125 Explain the collision theory and link to activation energy
Rates of reaction F 124-125 Describe and explain factors that affect rates of reaction (concentration, pressure, surface area, catalysts and temperature)
Rates of reaction F 125 Plot and interpret graphs showing rates of reactionRates of reaction F 124-125 Explain why one reactant is used in excess in a chemical reactionRates of reaction F 124-125 Describe what is meant by ‘a limiting reactant’
Rates of reaction F 125 RP Rates of Reaction: Investigate how changes in concentration affect the rates of reactions by measuring volume of the gas and change of colour
Rates of reaction F 126 Give examples of catalysts Rates of reaction F 121 Draw a reaction profile for a catalysed reaction
Reversible reactions F 126 Use the appropriate symbol to denote a reversible reactionReversible reactions F 126 Explain energy changes in reversible reactions (ammonium chloride and hydrated copper sulphate)Reversible reactions F 127 Explain what is meant by the term ‘equilibrium’
The Earths Early Atmosphere F 142 Describe the composition of the atmosphere and how long this has been the case
The Earths Early Atmosphere F 142-143 Describe the development from early atmosphere to present day
The Earths Early Atmosphere F 142-143 Draw links between the early Earth’s atmosphere and that of other planets (Mars and Venus)
The Earths Early Atmosphere F 144 Evaluate different theories regarding the Earth’s early atmosphere
The Earths Early Atmosphere F 143 Explain why oxygen levels increased and carbon dioxide levels decreased (linking to photosynthesis and
sedimentation)Global Warming F 144 Describe the term ‘greenhouse gases’ and give three examples (water vapour, carbon dioxide and methane)Global Warming F 144 Describe the ‘greenhouse effect’ linking to the wavelength of radiation
Global Warming F 144 Describe the effect of human activities on the levels of greenhouse gases, recalling two that affect methane and two that affect carbon dioxide
Global Warming F 145 Explain how peer review evidence have linked these activities to global climate change
Global Warming F 145 Explain why it is difficult to model this and how this has led to simplification, speculation and biased opinions in the media
Global Warming F 145 Describe 4 potential effects of global climate changeGlobal Warming F 145 Discuss the scale, risks and environmental implication of global climate changeGlobal Warming F 145 Describe what is meant by the term ‘carbon footprint’Global Warming F 145 Describe actions to reduce our carbon footprint and explain why these actions may have limited impact
Air pollution F 137 Describe combustion as a major source of atmospheric pollution
Air pollution F 137Name gases release when fuels such as coal are burnt (carbon dioxide, water vapour, carbon monoxide, sulphur dioxide and nitrogen oxides) and predict which of these would be produced from a given fuel composition
Air pollution F 137 Describe ‘particulates’ Air pollution F 137 Describe issues arising from carbon dioxide, sulphur dioxide, nitrogen oxides and particulates
Finite resources F 146 Recalls that humans use the Earth’s resources to provide; warmth, shelter, food, transport (through timber, clothing, fuels/energy and other materials)
Finite resources F 146 Define what is meant by the term ‘finite resource’
Finite resources F 146 Define what is meant by the term ‘sustainable development’ and explain the role that chemistry plays in developing agricultural and industrial processes
Finite resources F 147 Explain how some natural products are being replaced by some agricultural and synthetic productsWater and waste F 146-147 Describe the properties of potable water (is safe to drink) linking to purity, salt and microbe levels
Water and waste F 147 Describe the different sources of drinking water in the UK and the process that it must undergo before it is potable
Water and waste F 146 Describe the process of desalination (distillation or reverse osmosis)Water and waste F 147 Evaluate the methods to produce potable water (linking to location and potential water supply)Water and waste F 146-147 RP Water Purification: Analyse and purify water samples from different sources, including pH, dissolved solids
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and distillationWater and waste F 147 Explain why large amounts of waste water are produced (urban life styles and industrial processes)
Water and waste F 147 Explain what needs to be removed from sewage and agricultural waste in comparison with industrial waste water
Water and waste F 147 Describe the 4 steps of sewage treatmentWater and waste F 146-147 Compare the relative ease of obtaining potable water from waste, the ground and salt water
Life Cycle Assessments F 148 Describe what is meant by the term ‘life cycle assessment’
Life Cycle Assessments F 148 Describe the 4 stages of a life cycle assessment
Life Cycle Assessments F 148 Explain that water resources, energy and waste production can be easily quantified whereas pollutant effects
are hard to quantifyLife Cycle
Assessments F 148 Describe how simplified life cycle assessments can be used in a biased manner to support advertising claims in the media
Life Cycle Assessments F 148-149 Use data to carry out LCA for shopping bags made from plastic and paper
Life Cycle Assessments F 149 Explain how we can reduce our use of limited resources (reduce, reuse, recycle)
Making Materials F 149 Explain how to produce clay ceramicsMaking Materials F 149 Explain how glass is produced
Making Materials F 149 Discuss the environmental impact of using metal, glass, building materials, clay ceramics and plastics linking to the use of these limited resources and the energy used to extract and process them.
Making Materials F 149 Explain ways that we can reduce this environmental impactAlkanes and Alkenes F 136 Explain what crude oil is and how it is formedAlkanes and Alkenes F 136 Define ‘alkanes’ and give the general formulaAlkanes and Alkenes F 137 Recall the formulae and structures for the first 4 alkanes (methane, ethane, propane and butane)Alkanes and Alkenes F 138 Define ‘alkenes’ and give the general formula Alkanes and Alkenes F 138 Recall the formulae and structures for the first 4 alkenes (ethene, propene, butane, pentene)Alkanes and Alkenes F 136-139 Define the terms ‘saturated’ and ‘unsaturated’ and link to alkanes and alkenesAlkanes and Alkenes F 139 Use the bromine test to identify whether there are alkanes or alkenes presentFractional Distillation F 136 Explain the process of fractional distillation
Fractional Distillation F 136 Name and describe the uses (fuels and feedstock for the petrochemical industry e.g. solvents, lubricants, polymers and detergents) of each of the fractions produced (petrol, diesel, kerosene, heavy fuel oil and LPG)
Fractional Distillation F 136 Describe why carbon can form such a vast array of natural and synthetic compoundsFractional Distillation F 136 Explain how the size of hydrocarbon is linked to their boiling point, viscosity and flammability Fractional Distillation F 137 Describe the combustion of hydrocarbons and write balanced symbol equations
Cracking F 138 Describe what is meant by ‘cracking’Cracking F 138 Describe why cracking is requiredCracking F 138 Describe the methods and conditions used for ‘catalytic cracking’ and ‘steam cracking’Cracking F 138-139 Recall the uses of alkenes produced during cracking (polymers)Cracking F 138 Balance chemical equations for cracking
Lesson 1 Rates of reaction and reversible reactions. Knowledge
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Topic: Rates of reaction (10.3.3)
What are the two equations for calculating mean rate of reaction?
mean ROR = quantity of reactant used/time take
or quantity of product formed/time taken
If the mass of the product or reactant is given in grams, which unit should
you use for the rate?g/s
If the volume of the product or reactant is given in cm3, which unit
should you use for the rate?cm3/s
What does a steep gradient on a graph tell us about the rate of a reaction? The rate of reaction is fast
What does a flat line (0 gradient) on a graph tell us about the rate of a
reaction?The reaction has stopped
What has a higher surface area? A powder or lumps of a substance
Powder because more particles are exposed and able to successfully
collideState 4 factors that affect rate of
reactionPressure (in gases), concentration,
temperature, a catalyst
Topic: Reversible reactions (10.3.4)
What is a reversible reaction?A reaction that can go both forwards (to form the products) and backwards (to
form the reactants)
Give two examples of reversible reactions
Ammonium chloride ⇌ ammonia + hydrogen chloride
Hydrated copper sulphate (blue) ⇌ anhydrous copper sulphate (white) +
waterIs ammonium chloride -> ammonia + hydrogen chloride an endothermic or
exothermic reaction?Endothermic
What is it called when the forward and reverse reactions occur at exactly the
same rate?Equilibrium
What is the general equation for a reversible reaction? A + B ⇌ C + D
Which 3 factors affect the position of equilibrium?
Pressure (gases), temperature, concentration
What is a closed system? A reaction (system) where no reactants are added or products removed.
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Notes
Chemistry Revision: Rates of reaction
Chemistry Revision: Reversible Reactions
Chemistry Revision: Reversible Reactions
5
Notes
Key KnowledgeTWO equations for calculating rate of reaction:
Mean rate of reaction = ___________ Time taken
Mean rate of reaction = ____________ Time taken
Units for rate of reaction:
(a) .(b) .
5 factors that affect rate of reaction:1) C___________ 2) T____________3) C______________4) S_________ a________5) P___________(in gases)
Define: Activation energy:
Catalyst:
According to collision theory, particles must collide with enough ______________ to react.
Draw a reaction profile for a reaction with and without a catalyst.
Progress of reaction
Mastery Matrix PointsCalculate the mean rate of reaction Recall the units for mass (g), volume (cm3) and rate (g/s, cm3/sDraw tangents on curves in order to calculate rates of reactionExplain the collision theory and link to activation energyDescribe and explain factors that affect rates of reaction (concentration, pressure, surface area, catalysts and temperature)Plot and interpret graphs showing rates of reactionExplain why one reactant is used in excess in a chemical reactionDescribe what is meant by ‘a limiting reactant’RP Rates of Reaction: Investigate how changes in concentration affect the rates of reactions by measuring volume of the gas and change of colourGive examples of catalysts Draw a reaction profile for a catalysed reaction
Time (s) Volume of CO2 (cm3)
0 010 1020 1830 2440 3050 3560 3870 4080 4190 41100 41
2. a) Plot the graph to show these results. (b) Use it to calculate the rate of reaction at 15 seconds.
(c) Describe AND explain the pattern shown by the results.As time increases…
This is because…
3. Describe AND explain the effect of the 4 factors on rate of reaction:(a) Concentration. As the concentration increases…
(b) Temperature: As the temperature increases…
(c) Surface area: As the surface area increases…
(d) Catalyst: The presence of a catalyst…
1. In a reaction, 24cm3 of hydrogen gas is produced in 2 minutes. Calculate the rate of reaction.
2. Calculate rate of reaction AND write the word equation in each of these scenarios: (CHALLENGE: write symbol equations)(a) Sarah is reacting calcium carbonate with hydrochloric acid. She times
how much gas is produced in 2 minutes using a gas syringe. She finds that 45cm3 of gas is produced in this time. Give your answer to 2 s.f.
(b) Linda reacts 5g of magnesium with sulphuric acid. It takes 5 minutes for the magnesium to have reacted completed. Calculate the rate of reaction and give your answer to 2 s.f.
Energy
Volume of CO2 (cm3)
Time in ____________
Key Knowledge
Define:Reversible reactions:
Endothermic reaction: one that takes in ___________ from the surroundings, so the temperature ______________
Mastery Matrix Points
Use the appropriate symbol to denote a reversible reactionExplain energy changes in reversible reactions (ammonium chloride and hydrated copper sulphate)Explain what is meant by the term ‘equilibrium’
1. a) We can represent reversible reactions with an equation. Complete this equation below by adding in the correct type of arrow.
A + B _________ C(g) + D (g)
Guided Exam Question
Q1.Marble chips are mainly calcium carbonate (CaCO3).
A student investigated the rate of reaction between marble chips and hydrochloric acid (HCl).
Figure 1 shows the apparatus the student used.
Figure 1
(a) Complete and balance the equation for the reaction between marble chips and hydrochloric acid.
.................. + .................. → CaCl2 + .................. + ..................(2)
(b) The table below shows the student’s results.
Timein s
Volume of gasin dm3
0 0.000 30 0.030 60 0.046 90 0.052 120 0.065 150 0.070 180 0.076 210 0.079 240 0.080 270 0.080
On Figure 2:• Plot these results on the grid.• Draw a line of best fit.
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Key Knowledge
Define:Reversible reactions:
Endothermic reaction: one that takes in ___________ from the surroundings, so the temperature ______________
1. a) We can represent reversible reactions with an equation. Complete this equation below by adding in the correct type of arrow.
A + B _________ C(g) + D (g)
Figure 2
(4)
(c) Sketch a line on the grid in Figure 2 to show the results you would expect if the experiment was repeated using 20 g of smaller marble chips. Label this line A.
(2)
(d) Another student investigated the rate of reaction by measuring the change in mass. Figure 3 shows the graph plotted from this student’s results.
Figure 3
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Use Figure 3 to calculate the mean rate of the reaction up to the time the reaction is complete. Give your answer to three significant figures.
………………………….................................................................................................................................
………………………….................................................................................................................................
………………………….................................................................................................................................
………………………….................................................................................................................................
Mean rate of reaction = ........................................... g / s(4)
(e) Use Figure 3 to determine the rate of reaction at 150 seconds. Show your working on Figure 3.Give your answer in standard form.
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................
Rate of reaction at 150 s = ........................................... g / s(4)
Independent exam questions
Q2.Lithium carbonate reacts with dilute hydrochloric acid.
A group of students investigated the volume of gas produced.
This is the method used.
1. Place a known mass of lithium carbonate in a conical flask.2. Measure 10 cm3 of dilute hydrochloric acid using a measuring cylinder.3. Pour the acid into the conical flask.4. Place a bung in the flask and collect the gas as shown in Figure 1.
Figure 1
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(a) Figure 2 shows the measuring cylinder.
Figure 2
What volume of gas has been collected?
Volume = .......................................... cm3
(b) There was an anomaly in their results. What are the two possible reasons for the anomalous result.
Tick two boxes.
Too much lithium carbonate was added.
The bung was not pushed in firmly enough.
There was too much water in the trough.
The measuring cylinder was not completely over the delivery
The conical flask was too small.
Q3.A student investigated the effect of temperature on the rate of a reaction.
Figure 1 shows an experiment.
Figure 1
The student:
• put 50 cm3 sodium thiosulfate solution into a conical flask• heated the sodium thiosulfate solution to the required temperature
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• put the flask on a cross drawn on a piece of paper• added 5 cm3 dilute hydrochloric acid and started a stopclock• stopped the stopclock when the cross could no longer be seen• repeated the experiment at different temperatures.
The equation for the reaction is:
(a) Which product is a gas?
........................................................................(1)
(b) Figure 2 shows the results of this experiment at five different temperatures. The circled result point is anomalous.
Figure 2
(i) Draw a line of best fit on Figure 2 to show how the reaction time varied with reaction temperature.
(1)
(ii) Give a possible reason for the anomalous result at 40 °C.
...................................................................................................................
...................................................................................................................(1)
(iii) The reaction at 20 °C produced 0.32 g of sulfur in 64 seconds.
Calculate the rate of the reaction at 20 °C using the equation:
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...................................................................................................................
...................................................................................................................
...................................................................................................................
...................................................................................................................
Rate of reaction = .................................... grams per second(2)
(iv) Give two reasons why the rate of the reaction increases as the temperature increases.
Tick (✔) two boxes.
The particles move faster.
The particles collide less often.
All the particles have the same energy.
The particles collide with more energy.
The number of particles increases.
(2)
(v) Use the correct answer from the box to complete the sentence.
activation collision exothermic
The minimum amount of energy particles must have to react is called
the ................................................... energy.(1)
(Total 8 marks)
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Lesson 2. Gas tests and chromatography (10.3.5). Knowledge
Topic: Gas tests What is the gas test for oxygen
gas?A glowing splint will relight
What is the test for carbon dioxide gas?
Limewater will turn cloudy
What is the test for hydrogen gas? A burning splint will make a squeaky pop
What is the test for chlorine gas? When damp litmus paper is bleached and turns white
Topic: Chromatography
What is the aim of the experiment?Investigate the colours that are found within a mixture of food
colouringsWhat is the independent variable? Dye/ink colourWhat is the dependent variable? Rf value
Name 3 controls variables1) Start point of the colour2) Size of the coloured dot3) Start point of the solvent
Name 3 sources of error1) Starting line drawn in ink
2) Solvent above the starting line3) Dots too close together or too
bigWhy is a pencil used to draw the
starting line?To avoid any dye in a pen also
moving up the paperName 3 types of solvent that can
be used Water, alcohol and acetone
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Chemistry Revision: Gas tests and Chromatography
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Key KnowledgeGas tests:
Gas
Description of test Positive result
Negative result
O2
H2
CO2
Cl2
Key knowledgeChromatography
Chromatography can be used to separate __________and can give information to help identify substances. Chromatography involves a ___________phase and a __________phase. Separation depends on the distribution of ______________ between the phases.
Mastery Matrix Points Describe the gas test for carbon dioxide, hydrogen, oxygen and chlorineDescribe the two phases (stationary and mobile) of chromatography and its purposeCalculate Rf valuesInterpret chromatograms to decide whether a substance is pure of a mixtureRP Chromatography: Use paper chromatography to investigate the colours within different substances and calculate Rf values
Understanding and Explaining
1. Amy reacts two substances together which produces a gas. She bubbles this gas through limewater which turns cloudy and finds that damp litmus paper remains red. Explain how you know which gas Amy produced?Gas:_________Why:____________________________________________________________________________________________________________________________________________________________________
2. Look at the chromatogram below. State which food colourings are present and not present in the mixture X.
Food colourings present:______________________________________________________________Food colourings not present:___________________________________________________________
3. The chromatogram in Q2 showed that the solvent travelled 6cm up the chromatography paper. Food colouring A travelled 2cm up and D travelled 4cm up. Calculate the Rf value for A and D. Give your answer to 2s.f.
A=
D=
Key knowledgeChromatography
The equation for the Rf value is:
Different compounds have different Rf values in different _________, which can be used to help identify the ______________. The compounds in a mixture may ___________ into different spots depending on the _________ but a pure compound will produce a single ______ in all solvents.
Chromatography method:1. Draw a line in _______ 2cm up from
the bottom of the chromatography paper
2. Dot a sample of the substance you want to separate onto the line
3. Place the chromatography paper into a _______ containing a _________. Ensure that the solvent is below the _________ line.
4. Wait for the solvent (___________ phase) to travel up the paper.
5. If the substance separates into more than one _______ then the substance is ___________
6. If only single dot is observed, then the substance is not a mixture and is _____
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Notes
Guided Exam Questions- gas tests and chromatography
Guided Exam Questions
Q1.This question is about mixtures and analysis.
(a) Which two substances are mixtures?
Tick two boxes.
Air
Carbon dioxide
Graphite
Sodium Chloride
Steel
(2)
(b) Draw one line from each context to the correct meaning.
Context Meaning
A substance that has had nothingadded to it
Pure substance in chemistry
A single element or a single compound
A substance containing only atoms which have different numbers of protons
Pure substance in everyday life
A substance that can be separated by filtration
A useful product made by mixingsubstances
(2)
(c) What is the test for chlorine gas?
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Tick one box.
A glowing splint relights
A lighted splint gives a pop
Damp litmus paper turns white
Limewater turns milky
(1) (Total 5 marks)
Q2.A student investigated a food colouring using paper chromatography.
This is the method used.
1. Put a spot of food colouring X on the start line.2. Put spots of three separate dyes, A, B and C, on the start line.3. Place the bottom of the paper in water and leave it for several minutes.
(a) Figure 1 shows the apparatus the student used.
Figure 1
Give two mistakes the student made in setting up the experiment.
Tick two boxes.
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The lid was on the beaker.
The paper did not touch the bottom of the beaker.
The spots were too small.
The start line was drawn in ink.
The water level was above the spots.
(2)
(b) Another student set the experiment up correctly.
Figure 2 shows the student’s results.
Figure 2
How many dyes were in X?
Tick one box.
1 3 4 6
(1)
(c) Which dye, A, B or C, is not in X?
Write your answer in the box.
(1)
(d) Use Figure 2 to complete the table below.
Calculate the value for Rf for dye A.
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Distance in mm
Distance moved by dye A ..............................
Distance from start line to solvent front ..............................
Use the equation:
Give your answer to two significant figures.
........................................................................................................................
........................................................................................................................
........................................................................................................................
Rf value = ................................................................(5)
(Total 9 marks)Independent Exam Questions
Q3.Human stomachs contain hydrochloric acid.Stomach ache can be caused by too much acid in the stomach.Indigestion tablets can be used to reduce the amount of acid in the stomach.
(a) The graph shows how the volume of carbon dioxide produced changes with time, after some calcium carbonate is added to hydrochloric acid.
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(i) Complete the sentence to explain what happens between Oand P.
Between Oand Pthe calcium carbonate and hydrochloric acid .................(1)
(ii) Complete the sentence to explain what happens at P.
At Pthe calcium carbonate and hydrochloric acid ...................................
because ....................................................................................................(2)
(iii) Describe the test for carbon dioxide gas.
Test ........................................................................................................
Result of the test ....................................................................................(2)
(Total 5 marks)
Q4. Read the article.
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Problem food colouringsScientists say they have evidence that somefood colourings cause hyperactive behaviour inyoung children.
These food colourings are added to some sweets.
W, X, Y and Z are food colourings that may cause hyperactive behaviour in young children.
A scientist used chromatography to see if these food colourings were used in two sweets, S and P.
The results are shown on the chromatogram.
(a) Food colourings, such as W, X, Y and Z, are added to some sweets.
Suggest one reason why.
........................................................................................................................
........................................................................................................................(1)
(b) In chromatography, the Rf value =
Use the scale on the chromatogram to help you to answer this question.
Which food colouring, W, X, Y or Z, has an Rf value of 0.7?
(1)(c) From the chromatogram, what conclusions can the scientist make about the colourings in sweets S and P?
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........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................(3)
(Total 5 marks)
Lesson 3. The Earth’s early atmosphere and global warming. Knowledge
21
Topic: The Earth’s early atmosphere (10.3.6)When did the Early Atmosphere form? 4.6 billion years ago
State the four gases present in the Early Atmosphere?
Carbon dioxide (70%), methane (10%), ammonia (10%) and water vapour (10%)
Where did the gases in the early atmosphere come from? Volcanic activity
What are the 2 most prevalent gases in the atmosphere today? Nitrogen (78%) and Oxygen (21%)
State the 4 processes that lead to a reduction in CO2 between the Early
Atmosphere and today.
1) Dissolved in seas2) Trapped in rocks3) Photosynthesis
4) Trapped in fossil fuelsState the substances that have trapped
carbon dioxide under the ground Fossil Fuels and Sedimentary rocksName the process that caused an
increase in oxygen levels Photosynthesis
Topic: Global warming (10.3.7)Name the 3 greenhouse gases Water, Methane, carbon dioxide
State 3 human activities that increase the amount of methane in the
atmosphereDecaying organic matter, growing rice,
cattle farmingName the three types of radiation
emitted by the sunInfrared (long wave), visible light (short
wave) and UV (short wave)Name the one type of radiation emitted
by the Earth Infrared radiation (long wave)What happens to the majority of
radiation emitted by the sun when it gets to the Earth's atmosphere?
It passes through (is transmitted)
What happens to the majority of radiation emitted by the Earth when it
reaches the atmosphere?It is absorbed
State 2 human activities that increase the amount of carbon dioxide in the
atmosphereBurning fossil fuels, deforestation
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Chemistry Revision: The Earth’s Early Atmosphere
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Key KnowledgeState the 4 gases present in the Early Atmosphere 4.6 billion years ago:_____ % of C_________ d_________________% of M____________________% of A_________________________% of W______________ v_________
The atmosphere was very similar to the current atmosphere on two other planets M__________ and V________________. The majority of these gases are thought to have been produced by ________________.
Earth today, name the 2 most prevalent gases:
____% of ______________________________ % of _________________________(Very small amounts of ______________________________ %)
Name the process by which oceans are thought to have formed:
The process which caused oxygen levels to increase was ____________. This was carried out by _______ and algae.
Mastery Matrix Points Describe the composition of the atmosphere and how long this has been the caseDescribe the development from early atmosphere to present dayDraw links between the early Earth’s atmosphere and that of other planets (Mars and Venus)Evaluate different theories regarding the Earth’s early atmosphereExplain why oxygen levels increased and carbon dioxide levels decreased (linking to photosynthesis and sedimentation)
Understanding and Explaining1. Write the word and balanced symbol equation for photosynthesis.
2. Compare and contrast the composition of the current atmosphere to that of the atmosphere 4.6 billion years ago. Refer to the following gases: nitrogen, oxygen, carbon dioxide, water vapour, ammonia and methane
Early Atmosphere (4.6 billion years ago) Present atmosphere
3. The current atmosphere contains significantly more oxygen than the early atmosphere. Explain why by completing the paragraph and using the key words below: 2.7 billion years ago, green __________ and ______________- started to evolve. These organisms absorb ____________________ and produce ________________ in a process called _____________________________.Photosynthesis Algae Plants Carbon dioxide Oxygen
4. The current atmosphere contains significantly less carbon dioxide than the early atmosphere. State the 4 ways that is thought to have led to this decrease:
----
Chemistry Revision: Global warming
24
Key KnowledgeName the 3 main greenhouse gases:- w____________- m____________- c______________ d_______________
Name the 3 types of radiation emitted by the sun: ---
Name 2 human activities that increase the amount of:
(a) Methane:--
(b) Carbon dioxide:--State 4 potential effects of global climate change----Define ‘carbon footprint’:
State 3 ways to reduce our carbon footprint:---
What is the main cause of global climate change?
Mastery Matrix Points Describe the term ‘greenhouse gases’ and give three examples (water vapour, carbon dioxide and methane)Describe the ‘greenhouse effect’ linking to the wavelength of radiationDescribe the effect of human activities on the levels of greenhouse gases, recalling two that affect methane and two that affect carbon dioxideExplain how peer review evidence have linked these activities to global climate changeExplain why it is difficult to model this and how this has led to simplification, speculation and biased opinions in the mediaDescribe 4 potential effects of global climate changeDiscuss the scale, risks and environmental implication of global climate changeDescribe what is meant by the term ‘carbon footprint’Describe actions to reduce our carbon footprint and explain why these actions may have limited impact
Understanding and Explaining1. Complete the paragraph by using the key words below: The waves entering the atmosphere from the sun are made up of ___________ wavelength radiation that is easily able to pass through the atmosphere. Some of this is _____________ by the surface of the Earth whilst some is _______________ as _______________ wavelength radiation. This cannot pass through the atmosphere and so more is reflected back to the earth’s surface or absorbed causing the atmosphere to ___________ in temperature.
Increase short absorbed longer reflected
2. Explain why we need some greenhouse gases in our atmosphere.
3. Use the graph to describe the average global temperature between 1860and today.
Global average temperature has generally ______________________ between ______ and today.
1860= _____ ⁰CToday = _____⁰C
This is an increase of _____ ⁰C
Temperature has ___________________ (gone up and down) between these two dates.
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Notes
Guided Exam Question
Q1.This question is about the temperature of the Earth’s atmosphere.
(a) Give one reason why it is difficult to produce models for future climate change.
…………………………………..............................................................................................................................
………………………………….............................................................................................................................. (1)
(b) Describe how greenhouse gases help to maintain temperatures on Earth. Refer to radiation in your answer.
…………………………………..............................................................................................................................
…………………………………..............................................................................................................................
…………………………………..............................................................................................................................
…………………………………..............................................................................................................................
…………………………………..............................................................................................................................
………………………………….............................................................................................................................. (3)
(c) The figure below shows the change in mean global air temperature from 1860 to 2000.
Explain how human activities have contributed to the main trend shown from 1910 in the figure above. Describe the trend of the graph from 1910 in your answer
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................(3)
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Independent exam questions
Q2.Greenhouse gases affect the temperature of the Earth.(a) Which gas is a greenhouse gas?
Tick one box.
Argon
Methane
Nitrogen
Oxygen
(1)
(b) An increase in global temperature will cause climate change.What is one possible effect of climate change?
Tick one box.
Deforestation
Global dimming
Sea levels rising
Volcanic activity
(1)
(c) Carbon dioxide is also a greenhouse gas.The figure below shows how the concentration of carbon dioxide in the atmosphere has changed since 1850.
Which process is the reason for the change in carbon dioxide concentration shown on the figure above?
Tick one box.
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Burning of fossil fuels
Carbon capture
Formation of sedimentary rocks
Photosynthesis
(1)(d) Give three conclusions that can be made from the figure above. (hint- describe the 3
different patterns on the graph)1 .............................................................................................................................................................................................................................................2 .............................................................................................................................................................................................................................................3 .............................................................................................................................................................................................................................................
(3)(Total 6 marks)
Q3.Some theories suggest that the Earth’s early atmosphere was the same as Mars’ atmosphere today.The table below shows the percentage of four gases in the atmosphere of Mars today and the atmosphere of Earth today.
GasesThe atmosphere of
Mars today Earth today
Carbon dioxide 95.00% 0.04%
Nitrogen 3.50% 78.00%
Argon 1.00% 0.96%
Oxygen 0.50% 21.00%
(a) Which one of the gases in the table is a noble gas?........................................................................................................................
(1)(b) Draw a ring around the correct answer to complete each sentence.
(i) Noble gases are in Group
0
1
7
(1)
(ii) Noble gases are
slightly reactive.
unreactive.
very reactive.
(1)(c) The percentage of carbon dioxide in the Earth’s early atmosphere was 95.00%.
It is 0.04% in the Earth’s atmosphere today.(i) Calculate the decrease in the percentage of carbon dioxide in the Earth’s
atmosphere................................................................................................................
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...............................................................................................................
Decrease in percentage = ..............................%(1)
(ii) Give two reasons for this decrease................................................................................................................
...............................................................................................................
...............................................................................................................
............................................................................................................... (2)
(Total 6 marks)
4(a) Graph 1 shows how the percentage of carbon dioxide in the atmosphere changed in the last 4500 million years.
Use information from Graph 1 to answer these questions.(i) Describe how the percentage of carbon dioxide has changed in the last 4500
million years................................................................................................................
...............................................................................................................
...............................................................................................................
...............................................................................................................
(2)
(ii) Give two reasons why the percentage of carbon dioxide has changed................................................................................................................
...............................................................................................................
...............................................................................................................
............................................................................................................... (2)
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(c) Graph 2 shows how the percentage of carbon dioxide in the atmosphere changed in the last 250 years.
Should we be concerned about this change in the percentage of carbon dioxide?Explain your answer.........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
(2)
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Lesson 4. Finite resources and Air pollution
Topic: Global warming and air pollution (C.18)
Name the 3 greenhouse gases Water, Methane, carbon dioxide
State 3 human activities that increase the amount of methane in
the atmosphereDecaying organic matter, growing rice,
cattle farming
Name the three types of radiation emitted by the sun
Infrared (long wave), visible light (short wave) and UV (short wave)
Name the one type of radiation emitted by the Earth Infrared radiation (long wave)
Name the three types of radiation emitted by the sun
Infrared (long wave), visible light (short wave) and UV (short wave)
Name the one type of radiation emitted by the Earth Infrared radiation (long wave)
What happens to the majority of radiation emitted by the sun when it
gets to the Earth's atmosphere?It passes through (is transmitted)
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Chemistry Revision: Air Pollution and finite resources
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Key Knowledge
One of the biggest sources of atmospheric pollution is _________________ of fuels.
Five gases released into the atmosphere when a fuel is burned:-----Solid particles of hydrocarbons released into the atmosphere are called ________.Substance EffectsCarbon monoxide
Sulphur dioxide/ oxides of nitrogenParticulates
Humans use the Earth’s resources for 4 things:1)2)3)4)Term DefinitionFinite A resource that will _____
_____ and isn’t easily replaced
Renewable A resource that is easily __________.
Sustainable development
Development that meets the needs of ______ ___________without compromising the ability of future generations to meet their ______ _______.
Synthetic
Mastery Matrix Points Describe combustion as a major source of atmospheric pollutionName gases release when fuels such as coal are burnt (carbon dioxide, water vapour, carbon monoxide, sulphur dioxide and nitrogen oxides) and predict which of these would be produced from a given fuel compositionDescribe ‘particulates’ Describe issues arising from carbon dioxide, sulphur dioxide, nitrogen oxides and particulatesRecalls that humans use the Earth’s resources to provide; warmth, shelter, food, transport (through timber, clothing, fuels/energy and other materials) Define what is meant by the term ‘finite resource’Define what is meant by the term ‘sustainable development’ and explain the role that chemistry plays in developing agricultural and industrial processes
Understanding and Explaining 1. Coal is a fossil fuel. Coal contains the elements hydrogen, sulphur, oxygen and carbon. Name two products of burning
coal that have an impact on the environment. What impact does each of the products you named have on the environment?Product:__________ Impact:_________________________________________________________________________Product:__________ Impact:_________________________________________________________________________
2. Complete the following: Fuels react with oxygen to produce ____________and _________ this is called combustion. The reaction of a fuel with ________can produce a different oxide of carbon called _________________. This is produced when ____________ combustion occurs, this happens when the fuel does not burn in enough ____________.
3. Give two examples of synthetic materials that we instead of cotton and suggest why we use these.We can use _____ and ______ instead of cotton (natural) because______________________________________________________________________________________________________________________________________________
4. Recycling is viewed as being more sustainable than incinerating our waste or placing it into landfill sites. Give three reasons why recycling is better for the environment and future population than either of the alternatives.1.2.3.
5. Coal is described as a ‘finite’ resource. Explain why.Eventually coal will ___________ this means that ______________________________________________________
6. Using manure from cows is described as a ‘sustainable’ way of farming. Explain why.Cow manure is easily ___________ this means that ____________________________________________________
7. Wind turbines are very expensive to build yet the government has agreed £274 million of funding to build more wind farms around the UK. Suggest four reasons why they have made this decision.
- Reduces amount of________________ produced- It can be described as a ___________fuel (doesn’t rely on fossil fuels that will run out in the future)- ______________ but then cost of running relatively low- No ____________ or __________ will be produced so there is no contribution to acid rain
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Key Knowledge
One of the biggest sources of atmospheric pollution is _________________ of fuels.
Five gases released into the atmosphere when a fuel is burned:-----Solid particles of hydrocarbons released into the atmosphere are called ________.Substance EffectsCarbon monoxide
Sulphur dioxide/ oxides of nitrogenParticulates
Humans use the Earth’s resources for 4 things:1)2)3)4)Term DefinitionFinite A resource that will _____
_____ and isn’t easily replaced
Renewable A resource that is easily __________.
Sustainable development
Development that meets the needs of ______ ___________without compromising the ability of future generations to meet their ______ _______.
Synthetic
Notes
Guided Exam Question
Q1. In the future more coal-fired and fewer oil-fired power stations will be used to generate electricity.When coal and oil are burned they produce the same types of emissions which can cause environmental problems.
(a) Emissions from the chimney can cause acid rain, global dimming and global warming. Draw one straight line from each possible environmental problem to the emission that causes it.
Possible environmental problem Emission that causes it
carbon particles
acid rain
carbon dioxide
global warming
sulfur dioxide
global dimming
water vapour
........................................................................................................................(3)
(b) Draw a ring around the correct word in the box to complete each sentence.
carbon dioxide.
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(i) Incomplete combustion of coal or oil is caused by too little nitrogen.
oxygen.
(1)
carbon monoxide.
(ii) A gas formed by the incomplete combustion of coal or oil is hydrogen.
oxygen.
(1)
(c) The table shows the world production for both coal and oil in 2000.
The world production figures after 2000 are predicted.
Year World production of coal(billions of tonnes per year)
World production of oil (billions of barrels per year)
2000 3.5 12.5
2050 4.5 5.6
2100 5.0 1.7
2150 5.5 0.5
2200 6.0 0.0
(i) How is the world production of oil predicted to change from 2000 to 2200?
...............................................................................................................
...............................................................................................................(1)
(ii) Suggest two reasons why the world production of coal is predicted to increase.
1 ............................................................................................................
...............................................................................................................
2 ............................................................................................................
...............................................................................................................(2)
(Total 8 marks)
Independent Exam questions
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Q2. In the future:
• there will be fewer oil burning power stations
• there may be more wood burning power stations.
(a) Which one of the emissions from the chimney can cause acid rain?
........................................................................................................................(1)
(b) Draw a ring around the correct answer to complete the sentence.
acid rain.
Carbon particles in the Earth’s atmosphere cause global dimming.
global warming.
(1)
(c) Which gas in the air is needed for oil or wood to burn?
........................................................................................................................(1)
(d) Suggest why there will be fewer power stations burning oil in the future.
........................................................................................................................
........................................................................................................................(1)
(e) Some power stations burn wood.
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The wood comes from trees grown in forests.
Suggest why burning wood in power stations is said to be ‘carbon-neutral’.
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................(2)
(b) The table shows the percentage of electricity generated by different energy sources.
Energysources Renewables Nuclear Coal Gas and Oil
Percentage(%) 8 20 32 40
Complete the bar chart to show the percentage of electricity generated by coal and by gas and oil.
(2)(Total 8 marks)
Q3. There are millions of plastic bags in use. After use most of these plastic bags are buried in landfill sites. The amount sent to landfill could be reduced if the plastic bags:
• could be reused
• could be recycled by melting and making them into new plastic products
• could be burned to release energy.
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Use the information above and your knowledge and understanding to give the positive and negative environmental impacts of using these methods to reduce the amount of plastic bags sent to landfill.
Reuse means less bags will be used, the positive environmental impacts of this
are…………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
… However, the negative environmental impacts of this
are………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
..
Bags can be recycled this can have many positive environmental impacts such as
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
Conversely recycling does have some negative environmental impacts such as ………...
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
Bags can also be burned, the positive environmental impacts of this are………………….
………………………………………………………………………………………………………
………………………………………………………………………………………………………
However, there are many more negative environmental impacts such
as…………………..
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………(Total 6 marks)
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Lesson 5: Water and waste and Life cycle assessments.
Topic: Finite resources, water and waste (C.19)State 4 factors that humans use the Earth's resources for
Warmth, Shelter, Food, Transport
State 4 products gained from the Earth
Food, Timber, Clothing, Fuel
Define "finite" Will run outWhat is the name given to water that is safe to drink?
Potable
State the two stages of making potable water from a
lake or river
1) Filter bed2) Sterilise (with chlorine)
3) Add fluoride
Topic: Life cycle assessmentsWhat are the 4 stages of an LCA? 1) Extracting & processing raw
materials2) Manufacturing and packing
3) Use during its life4) Disposal
What does LCA stand for? Life Cycle Assessment What is the raw material of a plastic
bag?Crude Oil
What is the raw material of a paper bag?
Timber
Define LCAAn assessment of the environmental impact of a product over the course
of its life
When completing an LCA, what do scientists look at? 3 things
1) Amount of waste produced when making it 2) Amount of
CO2 used 3) Lifespan of the product
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Chemistry Revision: Life cycle assessments,waste and water
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Key KnowledgeLife cycle assessments (LCAs) are carried out to assess the environmental impact of products.
Name the 4 stages that must be evaluated during an LCA.1)
2)
3)
4)Define ‘potable’: __________________________________________________________________________________Two steps in producing potable water from ground (rain/fresh) water?1)
2)
Three substances that can be used to sterilise water:1. 2. 3.
Two steps of desalination of salty water?1)
2)
Two substances that must be removed from waste water from agriculture and sewage?1)2)Two substances that must be removed from industrial waste water?1)2)
Mastery Matrix Points Describe the 4 stages of a life cycle assessmentUse data to carry out LCA for shopping bags made from plastic and paperExplain how we can reduce our use of limited resources (reduce, reuse, recycle)Describe the properties of potable water (is safe to drink) linking to purity, salt and microbe levels Describe the different sources of drinking water in the UK and the process that it must undergo before it is potableDescribe the process of desalination (distillation or reverse osmosis)Evaluate the methods to produce potable water (linking to location and potential water supply)RP Water Purification: Analyse and purify water samples from different sources, including pH, dissolved solids and distillationExplain what needs to be removed from sewage and agricultural waste in comparison with industrial waste water Describe the 4 steps of sewage treatment
1. Use the information below to carry out a simple LCA for plastic and paper shopping bags. Use this to decide which is better for us to use and why. The number indicates the relative quantities e.g. paper bags require 4 times more water during their entire life time.
Conclusion: I think the plastic/ paper bag is better for us to use because________________________________________________________________________________________________________________________________________________________________________________
2. Describe the 4 stages of treating sewageScreening and __________________, sedimentation to produce _________________and __________, anaerobic digestion of _____________, __________biological treatment of effluent.
3. Fill in the table for the results you would expect when testing salt and distilled water:
Plastic Paper Statement comparing plastic and paper bagsConsumption of non-renewable energy
1 1.1
Consumption of water
1 4
Green house gas emissions
1 3.3
Solid waste produced
1 1.7
Average number of uses
10 2
Years taken to biodegrade
25 2
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Notes
Guided Exam Question
Q1.Water in Britain is taken from reservoirs to use as drinking water.
© KatieJonesPhotography/iStock/Thinkstock
(a) What are the two main steps used to treat water from reservoirs?
Give one reason for each step.
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................(4)
Read the article and then answer the questions.
Supermarkets launch eco-friendly plastic milk bags.Could this be the end of the milk bottle?
Milk bottles are made from glass or from plastic.
Glass milk bottles contain 0.5 litres of milk. When the milk is used up the emptybottles are returned to be re-used. Glass milk bottles are re-used 24 times onaverage. The glass to make new milk bottles is produced when a mixture of sand,limestone, soda and recycled glass is heated to about 1600 °C in a furnace. Thereare almost unlimited amounts of the raw materials needed to produce this glass.About 35% of used glass is recycled.
The most common plastic milk bottles contain 2 litres of milk. When the milk isused up the empty bottles are discarded as waste. The plastic used to make thesemilk bottles is poly(ethene). Poly(ethene) is produced from crude oil by first using
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fractional distillation, then cracking the naphtha fraction and finally polymerising theethene. About 5% of used poly(ethene) is recycled.
The new plastic milk bags contain 2 litres of milk. The milk bags are also madefrom poly(ethene). A milk bag uses 75% less poly(ethene) than is used to make thepoly(ethene) milk bottles. When the milk is used up the empty bags are discarded aswaste.
(b) Supermarkets claim that using milk bags instead of milk bottles would have less environmental impact.
Do you agree with this claim?
Use the information in the article and your knowledge and understanding to make appropriate comparisons to justify your answer.
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................(4)
(Total 8 marks)
Independent exam questions
Q2.Water from a lake in the UK is used to produce drinking water.
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(a) What are the two main steps used to treat water from lakes?
Give a reason for each step.
Step 1 ................................................................................................................
Reason .............................................................................................................
Step 2 ...............................................................................................................
Reason .............................................................................................................(2)
(b) Explain why it is more difficult to produce drinking water from waste water than from water in lakes.
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................
.............................................................................................................................(3)
(Total 5 marks)
Q3.Plastic and glass can be used to make milk bottles.
The figure below shows the percentage of milk bottles made from glass between 1975 and 2010.
(a) Plot the points and draw a line on the figure above to show the percentage of milk bottles made from materials other than glass between 1975 and 2010.
(3)
(b) The table below gives information about milk bottles.
Glass milk bottle Plastic milk bottle Raw materials Sand, limestone, Crude oil
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salt
Bottle material Soda-lime glass HD poly(ethene)
Initial stage inproduction of bottlematerial
Limestone and saltused to produce
sodium carbonate.
Production of naphtha fraction.
Maximum temperaturein production process
1600 °C 850 °C
Number of times bottle can be used for milk
25 1
Size(s) of bottle 0.5 dm3 0.5 dm3, 1 dm3, 2 dm3, 3 dm3
Percentage (%) of recycled material used in new bottles
50 % 10 %
Evaluate the production and use of bottles made from soda-lime glass and those made from HD poly(ethene).
Use the information given and your knowledge and understanding to justify your choice of material for milk bottles.
Glass bottles have ____ stages of production, these
are.............................................
………………………………………………………………………………………………
………………………………………………………………………………………………
On the other hand HD poly(ethene) bottles have ____ stages of production, these
are……………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
There is a __________ temperature in glass manufacture, this means that…………..
………………………………………………………………………………………………
….Glass bottles can be __________, and advantage of this
is…………………………….
………………………………………………………………………………………,
however……………………………………………………………………………………
………………………………………………………………………………………………
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The HD poly(ethene) has a great range
of……………………………………………….
………………………………………………………………………………………………..
Both the glass and HD poly(ethene) are produced
from………………………………..
……………………………………………………………………………………, however
glass bottles are made using a higher percentage of………………………………….
This means that……………………………………………………………………………
………………………………………………………………………………………………
In conclusion I think that the ___________ bottle is a better choice for a milk bottle
because……………………………………………………………………………………..
………………………………………………………………………………………………. (6)
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