Reflection - newmarketacademy.co.uk · Web viewLook at the rust word equation Iron + oxygen + water iron oxide. ... The word ‘exothermic’ comes from the Greek ‘ex’ meaning

Name: ______________________________ Class: ___________

Year 7 Topic 3a: Common Chemical Reactions (Chemistry)

Contents Contents.........................................................................................................................2What happens during chemical reactions?.....................................................................4

Cooking........................................................................................................................4Word equations...........................................................................................................5Rusting........................................................................................................................7Evidence of chemical reactions taking place.............................................................10

Temperature change..............................................................................................11Elements and the periodic table................................................................................14Atoms and outer electron shells................................................................................17

Chemical reactions: atoms getting stable outer shells...........................................18Three types of chemical bond...................................................................................20

Symbol equations.........................................................................................................21Conservation of mass...................................................................................................24

Balancing chemical equations...................................................................................27Atoms, molecules, elements and compounds..............................................................29

Elements and compounds.........................................................................................29Mixtures.....................................................................................................................30

Acids and bases............................................................................................................31Indicators...................................................................................................................31Acids..........................................................................................................................33Bases and alkalis.......................................................................................................34Neutralisation............................................................................................................35What are salts?..........................................................................................................38Acid + Metal oxide reactions.....................................................................................39Acid + Metal Carbonate reactions.............................................................................39

Limewater + carbon dioxide reaction...........................................................................40Acid + Metal reactions.................................................................................................41Hydrogen + Oxygen reaction: Squeaky pop test.........................................................41Aerobic Respiration......................................................................................................44Photosynthesis.............................................................................................................45Combustion of a hydrocarbon fuel...............................................................................46Knowledge Organiser Questions...................................................................................47

2

Prior knowledge1. A base is the opposite to…

a) An alkali b) An acid c) A salt d) A non-metal

e) A conductor

2. Stomach acid is a strong acid and would have a pH of?a) 2 b) 4 c) 7 d) 9 e) 14

3. Pure water is neutral and has a pH of?a) 2 b) 4 c) 7 d) 9 e) 14

4. A chemical used to tell us how acidic or basic (alkaline) something is?a) Hydrogen b) Glucose c) Salt d) Base e) Indicator

5. Reaction between an acid and alkali?a) Respiration b) Photosynth

esisc) Combustion d) Neutralisati

one) Rusting

6. An exothermic reaction between oxygen and glucose?a) Respiration b) Photosynth


one) Rusting

7. An endothermic reaction between carbon dioxide and water?a) Respiration b) Photosynth


one) Rusting

8. What does the mean in a chemical equationa) Equals b) Travels c) Turns into d) Energy

movese) To the right

9. When you burn 900g of wood, the ash remaining weighs only 600g. Why is this?a) Smoke

weighed 300g

b) 300g given off as light

c) Mass disappears

d) 300g of bonds broken

e) Particles get burnt

10. What does exothermic mean?a) Respiration b) Gives off

heatc) Takes in

heatd) Reactive e) Explosive

11. What is this reaction also known as burning: oxygen + hydrocarbon fuel carbon dioxide + water?a) Respiration b) Photosynth


one) Rusting

12. Products of a neutralisation reaction?a) Salt +

Hydrogenb) Carbon

dioxide + water

c) Glucose + oxygen

d) Salt + Water e) Iron oxide

13. Product of acid + metal reaction?a) Salt +

Hydrogenb) Carbon

dioxide + water

c) Glucose + oxygen


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14. The test for hydrogen gas?a) Squeaky

pop testb) Turns

limewater cloudy

c) Relights a glowing splint

d) Turns universal indicator red

e) Turns iodine black

15. Product of aerobic respiration?a) Salt +

Hydrogenb) Carbon

dioxide + water

c) Glucose + oxygen


ReflectionBefore the topic End of the topic Score: /

15What were you pleased with? What were you pleased with?

4

What happens during chemical reactions? A chemical equation describes what happens when atoms change how they are bonded with other atoms.We call these bonds chemical bonds and they are strong forces of attraction (caused by electrostatic forces) between the electrons in one atom and the positive nucleus of another.Different chemicals have different properties. We group properties up into two groups Physical and Chemical.

16. What happens to atoms during a chemical reaction?17. What force holds atoms together in a chemical bond?18. Negative charges are attracted to positive charges. What does attract mean?19. Which of the following are chemical properties and which are physical

properties?a) Colour b) Temperature c) Solid d) Similar reactione) All rust in air f) Do not react

easilyg) Smell funny h) Non-magnetic

Cooking When food is cooked the atoms in it are re-arranged. This is an example of a chemical reaction.

Often, we are breaking long chain molecules into smaller ones to help our digestive system. Cooking can also kill microbes in the food.

During cooking, we often get colour changes, smells, and gases produced. We cannot un-cook food.

20. Why might we want to kill microbes in our food?21. What is the name of this chemical reaction: glucose + oxygen carbon dioxide

+ water22. Our digestive system’s job is to break large molecules into small ones that can

be transported in our blood. Why do we need these molecules in our blood?

5

23. Describe some of the changes in physical properties of an egg as it cooksEgg Before cooking After cookingColourState of matter

Word equations Chemical reactions require ingredients (which we call reactants) to make new substances (which we call products). Different reactants make different products each with different properties. Those different products may then be reacted together to make new products again with different properties.A word equation for a reaction:Example from cooking reactions: Raw egg + Flour + Milk PancakeIn this way it is possible, even with only a few basic reactants, to make a huge variety of new chemicals (substances).On Earth we have only around 96 basic reactants we call elements. By combining them in different ways we can make an almost limitless number of different chemicals. We keep a list of all these elements in the periodic table.‘Element’ comes from the Greek ‘elementum’ meaning ‘first principle or most basic’.

24. The student has made some mistakes. Identify and correct themOriginal with mistakes Corrected

25. What does the arrow represent in a chemical equation?26. Approximately, how many different elements are there on Earth?6

27. Are there more metals or non-metals in the Periodic Table?

In 2005, a group from the University of Berne, in Switzerland, tried to determine the total number of stable chemicals made from just 5 elements (carbon, hydrogen, oxygen, nitrogen, and fluorine). They estimated just under 18 billion, but a subsequent analysis found they ignored many common chemicals, and their estimate should have been closer to 18000 billion.

More detailed word equationsWord equations are only allowed to contain words. No symbols or formulae such as CO2 are allowed in word equations.The names of products in a reaction can be hard to figure out. Here are some simple rules to follow when only two elements are reacting together.1. The name of the metal always comes first.2. If there are no metals then the element which is closest to the

left bottom corner of the periodic table goes first. 3. The end of the last non-metal name is often replaced with ‘ide’.

For example: Magnesium + oxygen Magnesium oxide

Hydrogen + sulfur Hydrogen SulfideSodium + chlorine Sodium chloride (also known as

table salt)4. Sometimes the prefixes mono, di or tri are also included. Eg.

Carbon monoxide and carbon dioxide. These give us information about the ratio of one substance to another in a chemical.

mono… – means one (monorail or monobrow) di… means two tri… mean three (triangle, triathlon, tricycle)

28. When water and carbon dioxide are made when methane reacts with oxygen.a) What are the reactants in the reaction above?b) What are the products in the reaction above?

29. Match the reactants to the correct products. Careful, three of the products do not match any reactants.

Oxygen + IronCarbon + OxygenChlorine + Lithium

Lithium chlorideIron oxygenLithium chlorateIron oxide

7

Sulfur + PotassiumNitrogen + Aluminium

Nitrogen aluminideCarbon dioxidePotassium sulfideAluminium nitride

30. Complete these word equationsa) Copper + Sulfur _____________________________________b) Iron + Nitrogen _____________________________________c) Chlorine + Carbon _____________________________________d) Calcium + Fluorine _____________________________________e) Cobalt + Chlorine _____________________________________f) Nickel + Oxygen _____________________________________

31. What does the arrow represent in a chemical equation?32. What does the arrow represent in this food chain: producer consumer?

Rusting Rusting is a chemical reaction between iron, oxygen and water. The chemical name for rust is iron oxide.Iron + oxygen + water Iron oxide (water is needed to enable this reaction)We can defend against rust by stopping oxygen or water getting to the iron. Paint as a barrier Oil as barrier Another metal as a barrier – e.g. zinc plated

33. How does using a barrier stop rusting happening?34. Look at the rust word equation Iron + oxygen + water iron oxide

a) What are the reactants of this reaction?b) What are the products of this reaction?

8

Investigating rusting

9

Use the structure strip below to write a method for this investigation and how it helped you decide.

35. Hypothesis being tested? (simple statement stating a relationship)

Conditions affect how quickly a nail rusts

36. Independent variable (you change)

37. Dependent variable (you will measure)

38. 3 control variables (ensures only the IV affects the DV – makes it fair)Do not pick same measuring device (ruler)

1)

2)

3)

44. Step by step method (start each line with a command verb e.g. measure, set-up, record)

1)

2)

3)

4)

5)

6)

56. Risk assessment(3 most obvious hazards in your experiment and how you will

1)

2)

10

reduce their risk) 3)

62. Record your results in the table below

ConditionsRust

afterwards?

How much rust?

Score /10Other notes

Control – in airWaterOil – no oxygen or waterBoiled water – no oxygenSalt water

63. Did these results show what you expected?64. Give one thing you might do to improve this experiment if you did it again?Controls in experiments

Experiments and investigations show us how two things are related (e.g. rust and conditions). We change only one thing (our independent variable) and then observe the effect on the other (our dependent variable).Controls are kept constant so we know that it is our independent variable that is having the effect and not something else.

65. What is the chemical name for rust?66. Which of these is the correct symbol for the element cobalt?

Co CO co C c Cob67. This student has made some mistakes. Identify and correct them.

The periodic table lists all the chemicals we know about.Most of the elements are metals their electrons cannot move. The columns going down are called groups. They tell us how many electrons shells an atom has.Each row of the periodic table is called a Period and tells us how many electron shells in total each atom has.The elements in the periodic table are in alphabetical order.

68. Match the correct variable to its definition below.Independent variable

A variable we keep the same in an investigation – to make the test fair

Dependent variable

The variable we change in an investigation

Control variable The variable we measure in an investigation

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Evidence of chemical reactions taking place When chemicals react, we often notice things happening which we can observe (see, hear, smell, measure). When the reaction is over everything settles down.Evidence of a chemical reaction can include some of the following: Unexpected temperature change – might get hotter or colder

Bubbles – a gas is being produced New Smell Colour changes Light given off Precipitate forms - a solid forms in a liquid. Often gets cloudy

69. Match the reaction to the evidence you might expect to observe. You can draw more than one line from each reaction.

Burning some paper

Temperature change

Bubbles - gas released

New smell – gas released

An iron gate rusting

Colour change

Light given off

Precipitate forms70. Are there more metals or non-metals in the periodic table?71. What happens to atoms during a reaction?72. This student has made some mistakes. Identify and correct.

Original with mistakes Corrected version

73. Look at the rust word equation: iron + oxygen + water iron oxide + watera) What are the reactants of this reaction?b) What are the products of this reaction?

74. Complete MultiChoice Questions Topic 7.1a. List 5Qs you are happy with and 5Qs you are not.

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Temperature change Exothermic reactions release heat. They feel hotter while the reaction takes place. E.g. respiration (we get hot when we exercise) and combustion

(burning).Endothermic reactions absorb heat. They feel colder while reactions take place. E.g. photosynthesis (absorbs light rather than heat) and medical

cold packs.

The word ‘exothermic’ comes from the Greek ‘ex’ meaning ‘out of inside’ (as in ‘exit’) and the word ‘thermic’ meaning ‘heat’. Teachers often use idea that exothermic ‘exits heat’.

The word ‘endothermic’ is similar but has starts with the Greek ‘en’ meaning ‘in’ (as in ‘enter’). Teachers often use idea that endothermic ‘enters heat’ into the products so must take it from outside.

75. How do can you tell if a reaction is exothermic?76. For each situation below, say if there is evidence of a chemical reaction taking

place?

Evidence of a chemical reaction?Ice melting – change of state

solidliquidHuman exercising and getting

hotA drum being hit – sound

releasedReminder how to use a measuring cylinder and how to ‘waft’ smells

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77. Why do we waft smells rather than inhale unknown gases?78. Complete these word equations:

a) Copper + Sulfur _____________________________________b) Iron + Nitrogen _____________________________________c) Chlorine + Carbon _____________________________________d) Calcium + Fluorine _____________________________________e) Cobalt + Chlorine _____________________________________f) Nickel + Oxygen _____________________________________g) ______________________ + ______________________ Aluminium sulfideh) ______________________ + ______________________ Carbon dioxidei) ______________________ + ______________________ Dihydrogen monoxide

Circus of chemical reactions79. Complete these two experiments and record your observations in the table

below.Observations Experiment 1 Acid + Metal Experiment 2 Acid + Milk

Temperature change seen? Increase or decrease?Bubbles seen – gas produced?New smell?Colour changes?Light given off?Precipitate forms - a solid forms in a liquid. Often gets cloudyMeasuring cylinder used

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correctly?Wafting technique for smelling used correctly?

Experiment 1: Acid + Metal

Experiment 2: Acid + Milk

Complete the structure strip below for the acid plus milk experiment80. Step by step

method (start each line with a command verb e.g. measure, set-up, record)

1)

2)

3)

4)

5)

6)

92. Risk assessment(3 most obvious

1)

15

hazards in your experiment and how you will reduce their risk)

2)

3)

98. Complete these word equationsa) Chlorine + carbon _____________________________________b) Copper + sulfur _____________________________________c) Iron + nitrogen _____________________________________d) Calcium + fluorine _____________________________________

Elements and the periodic table The periodic table lists all the elements we know. Each element has a symbol with one Capital letter. Some of the symbols are easy to remember such as C for Carbon. Some use Latin names so are more difficult to work out.

99. How many capital letters does each element chemical symbol have?100. Consider the aerobic respiration reaction which all living things do. Oxygen and

glucose are changed into carbon dioxide and water within the mitochondria of a cell.

a) What are the reactants in respiration?b) Write a word equation for respiration

The period table lists all of the elements we know. It puts them in order of atomic number (number of protons). Lithium ( Li3

7 ) has 3 protons. In a normal atom the number of electrons is the same as the number of protons.

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The big number is the atomic mass which is all the protons and neutrons combined. Li3

7 has a mass of 7. Since 3 of the mass are protons, it must have 4 neutrons.Most of the elements in the periodic table are metals. This means that they have electrons that can move (free electrons). They are on the left-hand side. Non-metals are on the right-hand side.The periodic table sorts elements in columns called Groups (). Elements in the same group have the same number of electrons in their outer shell and react in similar ways to each other.The rows are called Periods ( ). Elements in the same period have the same number of electron shells.

Elements in the middle of the periodic table are called Transition Metals and are a little more complicated. We will consider those in GCSE.

101. Do metals or non-metals have electrons that can move easily?102. Lithium is in Group 1 of the periodic table and has 1 electron in its outer shell.

How many electrons does Sodium (Na) have in its outer shell?103. Complete this table looking at the periodic table. The first row has been

completed for you.Element Symb

olNumber of protons

Atomic mass

Group Period Electrons in outer shell

Electron shells

Lithium Li37 3 7 1 2 1 2

a) Fluorineb) Potassiumc) Sodiumd) Magnesiu

me) Carbon

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History of the Periodic Table

Some of the more difficult symbols to rememberEnglish name

Symbol

Latin name

Where else we see this word today

Sodium Na NatriumPotassium K KaliumIron Fe Ferrum Ferrous – contains ironCopper Cu CuprumSilver Ag Argentiu

mGold Au AurumLead Pb Plumbum Plumber – used to use lead for pipesChlorine Cl Chlorum “Chloros” means pale green. Eg. chlorophyll,

chloroplastsHelium He Helium “Helious” means Sun. First detected in solar

spectrum in 1868.

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104. This student has made some mistakes. Identify and correct them.Original version with mistakes

Carbon dioxide is a gas made of the oxygen and dioxide elements.

Carbon has the symbol Ca. It is in group 4 so has 4 electron shells.

Oxygen is another word for air. It has no atomic mass because it is a gas.

Corrected version

105. Are there more metal or non-metal elements?106. Neither air nor steel are in the periodic table. What does this tell us about air

and steel?107. What does the word equation for photosynthesis tells us? carbon dioxide +

water glucose + oxygen

108. Complete MultiChoice Questions Topic 7.ba. List 5Qs you are happy with and 5Qs you are not.

109. Complete these word equations:a) Cobalt + Chlorine _____________________________________b) Nickel + Oxygen _____________________________________c) Zinc + Nitrogen _____________________________________d) ______________________ + ______________________ Aluminium sulfidee) ______________________ + ______________________ Carbon monoxidef) ______________________ + ______________________ Carbon dioxideg) ______________________ + ______________________ Dihydrogen monoxide

Atoms and outer electron shells In chemical reactions it is only the electrons in the outer shell of an atom that change things. Here we consider an atom of Lithium ( Li3

7 )Lithium is in Group 3 and Period 2 of the Periodic TableThis means it has 3 electrons in its outer shell and 2 shells in total.Here is an atom of Lithium ( Li3

7 ).

19

Rather than drawing the whole atom, we often simplify in one of these ways.

110. Why does the nucleus of an atom always have a +’ve charge?111. Complete the outer electron shells of the following atoms.

a) b) c) d) e)

f) g) h) i) j)

Chemical reactions: atoms getting stable outer shells Chemical reactions are caused by atoms trying to gain full or empty outer shells.

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Nitrogen is in Period 2 so has 2 electron shells. It is also in Group 5 so has 5 electrons in its outer shell. The number 5 is closer to 8 than 0 so nitrogen will gain 3 electrons to get a full outer shell.Aluminium is Period 3 so has 3 electron shells. It is in Group 3 so has 3 electrons in its outer shell. The number 3 is closer to 0 than to 8 so an aluminium atom will lose 3 electrons to get an empty shell.

Non-metals tend to be Groups 5-8 so tend to gain electrons.Metals tend to be in Groups 1 to 3 so always lose electronsGroup 4 atoms are special as they can behave like metals and non-metals as they are equally close to both 0 and 8. Hydrogen is also special as it only has 1 electron shell with 1 electron so will either gain or lose an electron.Group 0 is also known as Group 8. These atoms already have full outer shells. This makes them very unreactive. These non-metals are known as the Noble Gases.

112. Argon ( Ar1840 ) is in Period 3 and Group 0. It has an atomic

mass of 40 and an atomic number of 18. This means it has 18 electrons in total. Draw the electrons in their shells around Argon:

113. Why is Argon not reactive?

114. Use a period table to complete the following table for these atoms:

21

Li37 a) F9

19 b) Al1327 c) K19

39 d) Sr3888 e) Ar18

40 f) Mg1224

Group 1Electrons in outer shell = Group

1

Wants to lose or gain electrons?

Lose 1

115. Extended writing challenge. You score points by using key words. You can use words more than once.Neil deGrasse Tyson famously said that “We are all stardust”. He described how all the atoms in our bodies were made in stars which then exploded and sent across the universe. We are chemically related to all atoms in the universe.Explain how the atoms that make a 12year old may actually be billions of years old?

1 Point: Atoms Bonded

together2 Points:

Electrons Recycled

3 Points: Food chain Digestion

116. Complete the outer electron shells of the following atoms.

a) b) c) d) e)

f) g) h) i) j)

Three types of chemical bond All atoms can be sorted into the two groups metals and non-metals. All reactions involve atoms trying to get full or empty electron outer shells.There are only three combinations of atoms that are possible. This means there are only three types of bonds that can exist holding these atoms together.

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Ionic bonds: Metals + non-metalsMetal gives electrons. Non-metal takes electrons.Positive metal ions and negative non-metal ions.Covalent bonds: Non-metals + non-metalsNon-metals share electrons. No ions.Metallic bonds: Metals + metalsMetals give electrons to each other. Positive metal ions and delocalised electrons.

117. Which atoms are involved in chemical reactions?118. For each situation below, say if there is evidence of a chemical reaction taking

place?Evidence of a chemical reaction?

A chloroplast taking in light to allow photosynthesisWater freezing – change of state solidliquidWood combustingHuman exercising and getting hotA drum fallingA box being hit – sound released

119. Do we find metals on the left-hand or right-hand side of the period table?120. Why do we control some variables in an experiment?121. What type of chemical has electrons that are free (delocalised) and can move

easily?122. What do we call the type of chemical bonding involving metals and non-metals?123. Which electrons in an atom are involved in chemical reactions?124. Sketch diagrams of two atoms below. The first has been started for you.

Add as much further information to your diagrams as you can.Lithium ( Li3

7 ) Group 1, Period 2 Boron B511 Group 3, Period 2

23

125. Match the chemical bonds to the correct descriptionsIonic bonds Metal atoms only Electrons are free to move

around

Covalent bonds

Non-metal atoms only Electrons move to form ions

Metallic bonds

Non-metal and metals bond

Electrons are shared

126. Do non-metals tend to lose or gain electrons during a reaction?127. If an atom gains two electrons, what charge ion does it become?128. The student has made some mistakes. Identify and correct themOriginal with mistakes Corrected

Symbol equations Symbol equations are only allowed to contain symbols and formulae of chemicals. Each element must have only one capital letter at the start.Subscript numbers (small and low-down) following a chemical tell us how many of that atom there are in a certain molecule. We do not need to write 1 to show there is only one atom in something. Examples: Magnesium oxide, MgO – has 1 magnesium atom and 1 oxygen

atom Methane, CH4 – has 1 carbon atom and 4 hydrogen atoms Glucose, C6H12O6 – has 6 carbon atoms, 12 hydrogen atoms and

6 Oxygen atoms.Misconception 1: Students often forget to write subscript numbers. The two most common mistakes are: CO2 or CO2 both of which are incorrect versions of CO2.Misconception 2: Students sometimes change the subscript numbers when they are balancing equations. This is not allowed and is incorrect.

129. How many different types of element are there in each of the following molecules?

a) Hydrochloric acid (HCl)

b) Ethane (C2H6)

c) Hydrogen (H2)

d) Table salt (NaCl)

e) Dihydrogen f) Ammonia g) Sulfuric acid h) Aluminium 24

monoxide (H2O) (NH3) (H2SO4) oxide (Al2O3)

i) Sodium hydroxide (NaOH)

j) Ozone (O3)

k) Adrenaline (C9H13NO3)

l) Glucose (C6H12O6)

130. How many atoms are there in each of the following molecules?


b) Ethane (C2H6)

c) Hydrogen (H2)


e) Water (Dihydrogen monoxide) (H2O)

f) Ammonia (NH3)

g) Sulfuric acid (H2SO4)

h) Aluminium oxide (Al2O3)


j) Ozone (O3)



131. Describe the types of bonds formed when these reactants react together? The first is done for you.

Ionic bonding(metal +non-metal)

Covalent bonding(non-metals only)

Metallic bonding(metals only)

Carbon + Oxygen Carbon dioxide

Copper + Zinc Brass

Copper + Sulfur Copper sulfate

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Zinc + Fluorine Zinc Fluoride

Oxygen + Sulfur Sulfur dioxide

132. Which of these is the correct symbol for the element cobalt?Co CO co C c Cob


134. Complete MultiChoice Questions Topic 7.2a. List 5Qs you are happy with and 5Qs you are not.

135. Complete the word equation for respiration Oxygen + Glucose _________________________ + _________________________

136. Look at the KO Questions. Practice Look, Read, Cover, Write, Check for 5 minutes. Then work with your partner and test each other for another 5 minutes. Write a list of the 5Q numbers you are most confident with. Write another list with the 5Q you are least confident with.

Molecular massThe periodic table gives us the mass of each atom. We can use this to calculate the total mass of a molecule. Lithium Sulfate has the formula Li2S. This means that one molecule of lithium sulfate has 2 lithium atoms and 1 sulfur atom. Lithium ( Li3

7 ) has an atomic mass of 7 (of which 3 are protons)

Sulfur ( S1632 ) has an atomic mass of 32 (of which 16 are protons)The molecular mass of Lithium sulfate (Li2S) is the same as the mass of Li, S and S atoms combined. Molecular mass of Li2S = 7 + 7 + 32 = 46.

137. Use the periodic table to find the mass of each molecule. The first one has been done for you.

Sulfuric acid (H2SO4)

a) Ammonia (NH3)

b) Aluminium oxide (Al2O3)

c) Glucose (C6H12O6)

List different elements

H:S:O:

Number of each element

H: 2 S: 1O: 4

Atomic mass of each element from

H: 2 X 1 S: 1 X 32O: 4 X 16

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periodic tableTotal mass of each element in molecule

H: 2 X 1 = 2S: 1 X 32 = 32O: 4 X 16 = 64

Mass of molecule = Total mass of elements

2 + 32 + 64 = 98

d) Molecular mass of Sodium hydroxide (NaOH)?e) Molecular mass of Water (Dihydrogen monoxide) (H2O)?f) Molecular mass of Adrenaline (C9H13NO3)?138. Label this atom of Beryllium ( Be4

9 )with as much information as you can.

Conservation of mass In all chemical reactions, atoms rearrange themselves in different ways.Burning is a chemical reaction with oxygen called combustion. Eg.Burning iron filings: iron atoms bond with oxygen atoms in the air forming iron oxide.

The number of atoms of each element does not change during the reaction. Only how they are bonded together.Mass is a measure of the amount of matter (stuff) inside something. We measure mass in kg. The total mass cannot change in a chemical reaction.We call this the Law of Conservation of Mass. The mass of the products must equal the mass of the reactants.Remember that mass is not the same as weight which is the force acting on mass due to gravity. We measure weight in Newtons (N).

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Modelling a reaction with blocks

139. What is the law of conservation of mass?140. What is a more common name for a combustion reaction?141. The symbol equation for respiration is C6H12O6 + 6O2 6CO2 + 6H2O.If there are

36 atoms in total on the reactants side of the equation, how many must be on the product side?

142. If 6 atoms of carbon are stored within the products of a photosynthesis reaction, how many must have been in the reactants?

143. Which of these chemical names correctly match the symbols? Correct those that are wrong.

a) Carbon monoxideCo

b) Carbon dioxideCo2

c) Carbon monoxideCO2

d) Carbon dioxideCO2

e) Carbon dioxideCo2

f) Carbon dioxidecO2

g) Carbon monoxideCO2

h) Carbon dioxideCO2

How do some reactions seem to gain or lose gain mass?

Misconception: Some students wrongly think that gases have no mass. They do. The mass of the air pushing down on you is approximately 1000kg. Without it some of the fluids in our body would escape out of the tiny holes in our skin.

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Conservation of mass experiment 1: combustion of magnesiumBefore completing this experiment, write a method using the structure strip on the next page.144. Complete the word equation for the combustion of magnesium:

magnesium + ________________________ ________________________ ________________________

145. Complete this table during the experimentMass of crucible and magnesium before

reaction (g)

Mass of crucible and magnesium oxide after

reaction (g)Mass of oxygen in

magnesium oxide (g)

146. Step by step method(start each line with a command verb e.g. measure, set-up, reco22rd)

1)

2)

3)

4)

5)

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6)

158. Risk assessment(3 most obvious hazards in your experiment and how you will reduce their risk)

1)

2)

3)

Conservation of mass experiment 2: acid and carbonate

164. Complete this table during the experimentMass of conical flask and

reactants at start of reaction (g)

Mass of conical flask and products at end of reaction

(g)Mass of carbon dioxide gas

lost into the air (g)

Balancing chemical equations The law of conservation of mass tells us that the numbers of atoms of each element on both sides of a reaction must be the same. When we write symbol equations we need to ensure that both sides have the same number of atoms of each element. We call his balancing equations.When we do this, we can never change how a molecule is arranged. Never change subscript numbers after an element. E.g. H2O or

CO2

Only change the big number at start of each molecule. E.g.3H2O - means 3 molecules of H2O. (6 H and 3 O atoms in total)

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165. Which of these reactions are balanced? The first is done for you.Reaction 2H2 + O2

2H2Oa) CH4 + O2

H2O +CO2

b) Mg + O2 MgO

c) Li + N2 Li3N

Elements? H and O:

Atoms on both sides

H: 2x2=4O: 2

H:2x2=4O:2x1=2

Balanced? Yes

166. Use these atomic masses to calculate the molecular masses of the chemicals below.Hydrogen mass = 1; Carbon mass = 12; Oxygen mass = 16; Magnesium mass = 24a) H2O b) CO2 c) CH4 d) MgO

167. Has the student correctly balanced this reaction using the method above?

168. Use the method shown to balance these symbol equations.

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a) Na + Cl2 NaCl

b) C3H6 + O2 CO2 + H2O

c) Al + Fe3N2 AlN + Fe

d) O2 + H2 H2O e) Ga + N2 Ga3N2

f) Na + P Na3P

169. What is the law of conservation of mass?170. Balance these equations. Add the correct number of molecules below.

a) ….KOH + ….H3PO4 ….K3PO4 + ….H2O b) ….SnO2 + ….H2 ….Sn + ….H2O c) ….NH3 + ….O2 ….NO + ….H2O d) ….KNO3 + ….H2CO3 ….K2CO3 + ….HNO3 e) ….BF3 + ….Li2SO3 ….B2(SO3)3 + ….LiF f) ….B2Br6 + ….HNO3 ….B(NO3)3 + ….HBr HINT: [B(NO3)3] is [B(NOOO)

(NOOO) (NOOO)]

Atoms, molecules, elements and compounds Atoms are the simplest version of an element. They are small but not the smallest.

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Remember molecules are made of more than one atom chemically bonded together. Hydrogen molecules have the formula

H2. Water molecules have the formula

H2O. Carbon monoxide has the formula CO. Carbon dioxide has the formula CO2.

Elements and compounds Elements only contain one type of atom.All single atoms must be elements.Some molecules are also elements as they contain only one type of atom Eg. O2 contains two oxygen atoms.An element’s formula can only contain one Capital letter.

Compounds contain more than one element chemically bonded. All compounds must be molecules.A compound’s chemical formula must contain more than one Capital letter.

171. How can you tell that CH4 must be a compound just by looking at the capital letters?

172. Which of the following are elements, which are compounds?a) Nitrogen

molecule (N2)

b) Hydrogen (H2)

c) Table salt (NaCl)

d) Glucose (C6H12O6)

e) Hydrochloric acid (HCl)

f) Oxygen molecule (O2)

g) Adrenaline (C9H13NO3)


i) Ozone (O3)

j) Fluorine atom (F)

Mixtures Mixtures contain different chemicals that are not chemically bonded together.Mixtures may contain a mixture of compounds.

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173. Complete the word equation for the combustion of ironiron + ________________________ ________________________ ________________________

174. Extended writing challenge. You score points by using key words. You can use words more than once.Ancient cultures believed that all things came from one of four elements: Earth, Wind, Fire and Water.Alchemy gave rise to modern chemistry. It involved people trying to run metals into gold and caused people to look at the chemical ingredients around them.Describe how our ideas on elements have changed and how we would classify Earth, wind, fire and water today.

1 Point: Atoms One

2 Points: Compound of

hydrogen and oxygen

Mixtures3 Points:

Metals Mixture of gases

175. Compare compounds and mixtures. Use the visual organiser below.

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Acids and bases We can group chemicals in lots of ways such metals and non-metals. Another way we can group them is by their acidity. We measure acidity using the pH scale. pH stands for potential Hydrogen it has a lower-case p and a

capital H. We can measure from pH 1 to pH 14. All substances can be sorted into acid, base or neutral depending on their pH: Acids has a pH from 1-6 – vinegar and bee stings are acidic Neutral substances are pH 7 – pure water is neutral Bases are pH 8-14 – soap and wasp stings are basic (are bases)A base that is dissolved in water is called an alkali. Not all bases are alkalis, but all alkalis are bases.

176. What do we call a substance that is opposite to an acid?177. What pH is a neutral substance?178. Describe if these chemicals are acid, base (or alkali) or neutral?

a) Pure water

b) pH 3 c) lime juice d) pH 6 e) pH 7

f) hand wash

g) pH 12 h) Citric acid

i) pH 8 j) potential hydrogen of 14

Indicators To help us we identify substances as acidic, basic (alkaline) or neutral we use s indicators. There are different indicators to help us investigate different things. Red litmus indicator – turns blue when exposed to bases. Made

from lichen Blue litmus indicator – turns red when exposed to acids. Made

from lichen. Universal indicator – has a variety of possible colours to indicate

the pH of a substance. It turns green in neutral; Orange/Red in acid and Blue/Purple in base.

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179. Use colours to complete the indicator table above for red and blue litmus and universal indicator.

Testing the pH of substances using universal indicator180. Use the method below to complete the table.

Substance pH Description e.g. Strong acid

What colour would it turn red/blue

litmus?VinegarSoap solution

181. Complete the structure strip below for the testing pH experiment.Step by step method (start each line with a command verb e.g. measure, set-up, record)

1)

2)

3)

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4)

5)

6)

Acids Acids are sometimes corrosive. Can damage other substances through chemical reaction. They come in a variety of different strengths and their risk changes with that strength.The word ‘acid’ comes from the Latin ‘acidus’ meaning ‘sour or sharp’.Examples of acids include: battery acid (pH1); stomach acid (pH 2); Lemon juice (pH3); tomato juice (pH4); coffee (pH5); and, urine (pH 6).The two acids we use most commonly in science lessons are: Hydrochloric acid (HCl)

the same chemical as the acid in your stomach Sulfuric acid (H2SO4)

made of 2 hydrogen, a sulfur atom and 4 oxygen atoms.

Acids are acids because they produce H+

ions when dissolved in water. Hydrogen ions have a missing electron. They steal electrons from other substances during a reaction.

Ions are atoms with more less electrons than they should have.

193. What pH are acids?194. What do we call the chemical that is the opposite of an acid?195. What do we call a chemical that changes colour in acid or base?196. How can you tell that CH4 must be a compound just by looking at the capital

letters?197. Which of the following are elements, which are compounds?

a) Nitrogen molecule (N2)

b) Hydrogen (H2)




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i) Ozone (O3)



199. Complete MultiChoice Questions Topic 7.2b. List 5Qs you are happy with and 5Qs you are not.

200. Complete this diagram of a Lithium atom ( Li37 ). Add as much information as you

can.

Bases and alkalis Bases (and alkalis) will react with acids and neutralise them.Alkalis are bases that are dissolved in water.Often the term base and alkali are interchanged incorrectly. Not all bases dissolve in water so not all bases are alkalis.The bases we use most often is science are metal oxides and metal hydroxides. Metal hydroxides are dissolved in water so are also alkali.Strong bases can be caustic. They can burn or corrode living tissue by chemical reaction. The warning symbol for caustic and corrosive are the same.Example of alkalis include: drain cleaner (pH 14); bleach (pH 13); soap (pH 10); baking soda (pH 9); and, blood (pH 7.4)

Alkalis contain hydroxide ions (OH–). These are molecules of oxygen and hydrogen with one too many electrons. They try and give electrons to other substances during a chemical reaction.

201. What do bases and alkalis do to acids?202. What pH are based and alkalis?203. Describe if these chemicals are acid, base (or alkali) or neutral?

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a) Pure water b) Urine c) Blood d) Vinegar e) Your stomach

f) hand wash g) pH 12 h) pH 7 i) pH 8 j) tomato juice

204. Match the chemical bonds to the correct descriptionsIonic bonds Metal atoms only Electrons are free to move

around

Covalent bonds

Non-metal atoms only Electrons move to form ions

Metallic bonds

Non-metal and metals bond

Electrons are shared

205. How many atoms are there in the following chemicals?a) N2 b) O3 c) CaO d) F2 e) CH4

206. How many different types of element are there in each of the following molecules?


b) Ethane (C2H6)

c) Hydrogen (H2)


e) Dihydrogen monoxide (H2O)

f) Ammonia (NH3)

g) Sulfuric acid (H2SO4)



j) Ozone (O3)




Neutralisation Neutralisation is an exothermic reaction. It gives out heat.When acids and bases or acids and alkalis react, they neutralise each other. This means they make each other weaker. In the right amounts they will neutralise each other entirely. When this happens, you are left with water (a neutral solution) and another substance we call a salt.

Acid + Base Salt + Water

Neutralisation happens in our stomachs when our basic (alkaline) saliva meets our acidic stomach acid.

208. What happens to pH of an acid during neutralisation?209. What happens to pH of an alkali during neutralisation?

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210. What colour does universal indicator turn in a neutral solution?211. What two products are always made when an acid and a base react?212. How can you tell if a reaction is exothermic?213. How can you tell if a reaction is endothermic?214. Which of the following are elements, which are compounds?

a) Nitrogen molecule (N2)

b) Hydrogen (H2)







i) Ozone (O3)


215. What type of chemical bonds form between two non-metals sharing electrons?216. What types of elements bond involve metals and non-metal and create ions?217. Complete this table comparing neutrons, protons, and electrons

Location in atom Mass ChargeNeutronProtonElectron

218. What two chemicals are the reactants in a neutralisation reaction?219. What two chemicals are the products of a neutralisation reaction?220. What do we call a base that is dissolved in water?221. How many electrons do atoms want in their 1st, 2nd and 3rd shells?222. Which of these may be evidence of a chemical reaction happening?

a) Bubbles b) Colour change c) Melting d) Dissolvinge) Heat released f) Light releases g) New smell h) Falling

223. There are some mistakes in the products of these chemical equations. Identify and correct.

a) Nickel + oxygen oxygen nicklide

b) Chlorine + zinc zinc chloride + water

c) Sulfur + iron iron sulfate

d) Oxygen + hydrogen carbon dioxide

Watching neutralisation happening: rainbow fizz224. After the practical record your competent in your practical skills in the table

below.

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Practical skill Not able Able with reminder

Able without

reminderSafety measures followed at all time? Including using test tube rack to avoid rolling test tubesMeasuring cylinder used correctly?Dropper used to measure correctly?Cross contamination of droppers avoided?

225. Use the structure strip on the following page to write a method for the experiment below.

226. Why do we try and avoid cross-contamination (getting acid/alkali on the same dropper)?

227. Step by step method (start each line with a command verb e.g. measure, set-up, record)

1)

2)

3)

4)

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5)

6)

239. Risk assessment(3 most obvious hazards in your experiment and how you will reduce their risk)

1)

2)

3)

245. During this experiment why was the Universal indicator changing colour?246. What evidence was there of a gas being produced in this reaction?247. This student has made a mistake balancing this equation. Identify and correct it.

What are salts? A salt is a compound formed during a neutralisation reaction. It has the hydrogen in the acid replaced by the metal from the base. Hydrochloric acid makes metal chloride salts (contain metal and

chlorine atoms) Sulfuric acid makes metal sulfate salts (contain metal, sulfur and

oxygen atoms)Example neutralisation reactions: Sodium hydroxide + sulfuric acid sodium sulfate + water

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Hydrochloric acid + Potassium Hydroxide Potassium chloride + Water

How to work out the products from a neutralisation reaction:

248. Complete these word equations:a) Lithium hydroxide + hydrochloric acid _____________ + _____________

_____________b) Hydrochloric acid + potassium hydroxide _____________ + _____________

_____________c) Lithium hydroxide + sulfuric acid _____________ + _____________

_____________d) Sulfuric acid + potassium hydroxide _____________ + _____________

_____________e) Sulfuric acid + sodium hydroxide _____________ + _____________

_____________f) _____________ _____________ + _____________ _____________ Tin chloride +

waterg) _____________ _____________ + _____________ _____________ Water + nickel

sulfateh) _____________ _____________ + _____________ _____________ Zinc sulfate +

wateri) _____________ _____________ + _____________ _____________ Water + iron

chloride

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Acid + Metal oxide reactions Acid and metal oxide reactions are exothermic. They release heat.They are also neutralisation reactions.Metal oxides are bases but do not dissolve in water (are insoluble) so are not alkalis.

Acid + Metal oxide Salt + Watere.g. Hydrochloric acid + Magnesium oxide Magnesium chloride + Water

249. Complete these word equations:a) Iron oxide + hydrochloric acid _____________ + _____________

_____________b) Hydrochloric acid + nickel oxide _____________ + _____________

_____________c) Calcium hydroxide + sulfuric acid _____________ + _____________

_____________d) Sulfuric acid + tin oxide _____________ + _____________ _____________

250. What two errors are there in this word equation: Sulfuric acid + iron = iron sulfate + H2O

Acid + Metal Carbonate reactions Acid and metal carbonate reactions are exothermic. They release heat.They are another type of neutralisation reaction. So form a salt and water.The word ‘carbonate’ tells us there is carbon and oxygen present. The carbon reacts with oxygen to form carbon dioxide

Acid + Metal carbonate Salt + Water + Carbon dioxidee.g. Hydrochloric acid + Zinc carbonate Zinc chloride + Water + Carbon dioxide

251. Complete these word equations:44

a) __________ __________ + __________ __________ water + iron chloride + carbon dioxide

b) Zinc carbonate + sulfuric acid _________ + _________ _________ + _________ __________

c) Iron oxide + sulfuric acid _____________ + _____________ _____________d) Sulfuric acid + nickel oxide _____________ + _____________

_____________e) Calcium hydroxide + hydrochloric acid _____________ + _____________

_____________

Limewater + carbon dioxide reaction We use limewater to test for the presence of carbon dioxide.

Limewater + carbon dioxide calcium carbonate + waterDuring this reaction a precipitate is formed (calcium carbonate). We see this solid precipitate as the limewater becomes cloudy.

Acid plus metal carbonate experiment

Complete the structure strip below for the acid plus metal carbonate experiment252. Risk

assessment(3 most obvious hazards in your experiment and how you will

1)

2)

45

reduce their risk) 3)

258. What happens to limewater in the presence of carbon dioxide?259. What does the term …carbonate tell us about a chemical?260. What is the opposite of a base?261. What pH are bases?262. What colour does Universal indicator turn in a strong base?

Acid + Metal reactions Acid and metal reactions are exothermic. They release heat.Metal is not a base. There are no oxygen atoms to bond with the acid’s hydrogen. Therefore, no water can be formed.

Acid + Metal Salt + Hydrogene.g. Hydrochloric acid + potassium potassium chloride + hydrogen

Hydrogen + Oxygen reaction: Squeaky pop test We can test for hydrogen gas using a test called the squeaky pop test.It involves catching the hydrogen created and reacting it with oxygen by burning it.It is an exothermic reaction and releases heat and sound. It makes a squeaky pop.Hydrogen + oxygen water

263. What two gases react in the squeaky pop test?

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264. Complete these word equations.a) Magnesium + hydrochloric acid _____________ + _____________

_____________b) Sulfuric acid + iron _____________ + _____________ _____________c) _____________ + _____________ _____________ copper sulfate + hydrogend) Zinc carbonate + sulfuric acid _________ + _________ _________ + _________

__________e) Iron oxide + sulfuric acid _____________ + _____________ _____________

265. What is a precipitate?266. What is the difference between exothermic and endothermic reactions?267. What reacts with limewater to make it form a white precipitation and go cloudy?268. Balance the following symbol equations

a) Mg + HCl MgCl2 + H2 b) H2 + O2 H2O

c) Na + HCl NaCl+ H2O d) BeO + HCl BeCl2 + H2O

e) LiOH + HCl LiCl + H2O f) CaCO3 + HCl CaCl2 + H2O + CO2

269. What atoms do all carbonates contain?270. Match the technique to the substance being tested for:

Makes a squeaky pop noise Strong acid47

when lit

Turns universal indicator red Alkali

Turns limewater cloudy Hydrogen

Turns red-litmus paper blue Carbon dioxide gas

The squeaky pop test is the same

exothermic and explosive reaction that many space rockets use to propel themselves into space.

In this picture, the space shuttle has three fuel tanks attached: one red in the middle (Oxygen) and two white (Hydrogen).

They are mixed and ignited.

The gas is forced downwards by the shuttle.

This causes a huge thrust force upwards which accelerates the shuttle upward gas (Newton’s 3rd Law).

The cloud, is water vapour. Oxygen + Hydrogen Water.

Acid plus metal experiment

271. Before completing this experiment use the structure strip to complete a risk assessment

272. Risk assessment(3 most obvious hazards in your

1)

2)

48

experiment and how you will reduce their risk) 3)

278. Extended writing challenge. You score points by using key words. You can use words more than once.Tomato ketchup contains an acid called acetic acid.If you put a tarnished coin in ketchup it comes out shiny and new-looking. If you kept using the same ketchup over and over again, eventually it would not taste the same.Can you explain what is going on here? Use word equations to help.

1 Point: Reactants Rearranged

2 Points: Salt Mass of

products3 Points:

H+ ions Exothermic

279. Complete these word equations.a) Sulfuric acid + Zinc oxide b) Hydrochloric acid + Iron Carbonate c) Hydrochloric acid + Lead hydroxide d) Sulfuric acid + Calcium e) Hydrogen + Oxygen

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Aerobic Respiration All living organisms do this. Every cell in your body is doing it right now.Mitochondria in our cells perform this exothermic reaction. In which glucose (C6H12O6) reacts with oxygen (O2) to produce Carbon Dioxide (CO2) and Water (H2O).

Glucose + Oxygen Carbon dioxide + WaterMuch of our body’s design is around this reaction:

Our digestive system gets glucose from food into our blood.Enzymes break carbohydrates into smaller molecules which then diffuse through our small intestine wall and into our blood.

Our respiratory system gets oxygen from air into our blood. Oxygen diffuses through the alveoli in our lungs into our blood. At the same time, carbon dioxide diffuses out of our blood in air we breathe out.

Our circulatory system uses blood to carry the reactants to our cells and to carry the products back. Red blood cells are specialised cells which carry oxygen.

280. How can you tell if a reaction is exothermic or endothermic?Testing respiration for release of carbon dioxide

281. What is a precipitate?50

282. What is the word equation for respiration?283. Which part of a cell is responsible for most respiration?

51

Photosynthesis Green plants and algae are producers. They make glucose using photosynthesis.Photosynthesis is an endothermic reaction. Green chloroplasts in cells (absorb light not heat). Carbon dioxide and water and then react to form glucose and oxygen.

Carbon dioxide + Water Glucose + OxygenGreen plants and algae also respire as they are living organisms.

Some gardeners speak to their plants in a bid to make them grow better. Prince Charles was a famous advocate of this. Science suggests this may provide additional carbon dioxide in our breath which may promote photosynthesis and growth.

284. What is the word equation for photosynthesis?285. Consider this food chain

Flower Butterfly Blue tit Kestrela) What is the producer in this food chain?b) What is the primary consumer?c) What do the arrows represent?

286. What part of a plant cell carries out photosynthesis?287. Do plants use respiration, photosynthesis or both?288. Compare photosynthesis and respiration reactions using the visual organiser

below.

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Complete Combustion of a hydrocarbon fuel Complete combustion in the science term for burning. It is an exothermic reaction in which fuel is reacted with oxygen.Hydrocarbons are molecules which contain only hydrogen and carbon. Coal, oil and gas are hydrocarbons.

Hydrocarbon fuel + oxygen carbon dioxide + water

The combustion engine uses explosions contained inside a cylinder with pistons to provide a thrust force to accelerate a vehicle. You can often see tiny amounts of water dripping from the exhaust of vehicles. The noise we hear from cars and other road vehicles is actually the combination of lots of small explosions. One issue with burning petrol and diesel is that they contain additional substances which then produce harmful substances such as sulfur dioxide.

290. Methane gas is a hydrocarbon CH4.What is a hydrocarbon?291. How many atoms are there in a molecule of methane (CH4)?292. What is an exothermic reactionTesting combustion for release of carbon dioxide and water

293. What are the products of combustion of a hydrocarbon fuel?294. Match the descriptions to the correct state of matter

High speed particles Solid Strong forces hold

particles in fixed position

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Particles vibrate

around fixed point

Liquid Weak forces of attraction between particles

Particles able to slide past each other

GasForces of attraction hold particles close bu not in

fixed positionKnowledge Organiser Questions KQ.1. When atoms change how they are bonded with

other atoms? Chemical reaction

KQ.2. A symbol meaning ‘turns into’ in a reaction

KQ.3. The ingredients used in a chemical reaction Reactants

KQ.4. The new chemicals made in a chemical reaction ProductsKQ.5. Substances which have free electrons and form

+’ve ions MetalsKQ.6. Substances which do not have free electrons.

Form -’ve ions? Non-metals

KQ.7. The periodic table contains a list of all known…. Elements

KQ.8. A chemical ending with ‘… oxide ‘ must contain? Oxygen atomsKQ.9. A chemical ending with ‘… chlorate ‘ must

contain?Chlorine and oxygen atoms

KQ.10. A chemical ending with ‘… hydroxide ‘ must contain?

Hydrogen and oxygen atoms

KQ.11. The chemical name for rust? Iron oxideKQ.12. How many capital letters does the symbol of

each element have? One capital letter

KQ.13. One or more atoms bonded together? MoleculeKQ.14. One of more different type of element

bonded together? CompoundKQ.15. Chemical reactions that release heat and

feel warm? Exothermic reactionKQ.16. Chemical reactions that take in heat and

feel cold? Endothermic reactionKQ.17. An exothermic reaction used by all living

things? RespirationKQ.18. An endothermic reaction used by plants to

make glucose? PhotosynthesisKQ.19. Where our eyes should be to measure

volume in a measuring cylinderAt eye level with top of liquid

KQ.20. How we safely smell a gas in science? WaftKQ.21. Bubbles in a liquid are a sign of during a

reaction? Gas being produced

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KQ.22. How do we test for carbon dioxide gas? It turns limewater cloudy

KQ.23. How do we test for hydrogen gas? It makes a squeaky pop when lit

KQ.24. Iron + Nitrogen Iron nitrate

KQ.25. Acid used to make sodium chloride? Hydrochloric acid

KQ.26. The columns of the period table are called? Groups

KQ.27. The rows of the periodic table are called? Periods

KQ.28. The group number of an element tells us… Electrons in outer shell

KQ.29. The period number of an element tells us… Number of electron shellsKQ.30. The big number next to an element in the

periodic table? Atomic massKQ.31. The smaller number next to an element in

the periodic table?Atomic number (number of protons)

KQ.32. An atom with more or less electrons that protons? An ion

KQ.33. The mass of the reactants = mass of products is called?

Law of conservation of mass

KQ.34. Number of electrons atoms want in their 1st, 2nd and 3rd electron shells? 2, 8, 8

KQ.35. Mass of 1, charge of +1, found in the nucleus of atom? Proton

KQ.36. Mass of 1, charge of 0, found in the nucleus of atom? Neutron

KQ.37. Mass of almost 0, charge of -1, be found in shells around the nucleus of an atom? Electron

KQ.38. When products seem to have less mass than reactants? Gas escaped

KQ.39. When products seem to have more mass than reactants?

Gas in the air is a reactant

KQ.40. Contain only one type of atom? ElementKQ.41. A substance that help us test for acids and

bases? Indicator

KQ.42. Opposite of an acid? Base (or alkali)

KQ.43. pH of 7? Neutral

KQ.44. pH of a strong acid? 1

KQ.45. pH of a strong alkali? 14KQ.46. Name of the reaction when acid + alkali

salt + water Neutralisation

KQ.47. Acid + Alkali Salt + Water

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KQ.48. Acid + Metal Salt + Hydrogen

KQ.49. Acid + Metal Carbonate Salt + Water + Carbon dioxide

KQ.50. Hydrocarbon fuel + Oxygen Carbon dioxide + Water

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Documents

Reflection - newmarketacademy.co.uk · Web viewLook at the rust word equation Iron + oxygen + water iron oxide. ... The word ‘exothermic’ comes from the Greek ‘ex’ meaning