COMPLETE 2024 AQA GCSE
CHEMISTRY – PAPER 2
ACTUAL EXAM WITH COMPLETE
SOLUTIONS RATED A
Addition polymerisation - ✔✔✔ ANSWER > Only one monomer type
Only one product formed
C=C bond in monomer
Advantage of phytomining & bioleaching - ✔✔✔ ANSWER > They have a much
smaller impact on the environment
Advantages of using machines for tests - ✔✔✔ ANSWER > 1) Very sensitive -
they can detect even the tiniest amounts of substances
2) Very fast - tests can be automated
3) Very accurate
Alloys - Aluminium alloys - ✔✔✔ ANSWER > Aluminium has a low density -
important property in aircraft manufacture
Pure aluminium is too soft aeroplanes - allowed with small amounts of other
metals to make it stronger
Alloys - Brass - ✔✔✔ ANSWER > Copper + Zinc
More malleable than bronze
Used in situations where lower friction is required e.g. water taps & door
fittings Alloys - Bronze - ✔✔✔ ANSWER > Copper + Tin
Harder than copper
Used to make medals, decorative ornaments & statues
Alloys - Gold alloys - ✔✔✔ ANSWER > Pure gold is very soft - metals such as
zinc, copper & silver are used to harden it
Used to make jewellery
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,Aluminium rusting - ✔✔✔ ANSWER > Aluminium corrodes when exposed to air
Aluminium objects aren't completely destroyed by corrosion - the aluminium
oxide that forms doesn't flake away, but it forms a nice protective layer that
sticks firmly to the aluminium below and stops any further reaction taking
place
Ammonium nitrate formula - ✔✔✔ ANSWER > Ammonia + Nitric Acid -->
Ammonium Nitrate
NH3(aq) + HNO3(aq) --> NH4NO3(aq)
Ammonium nitrate reaction - in industry - ✔✔✔ ANSWER > Carried out in
giant vats at high concentrations -results in a very exothermic reaction
Heat released is used to evaporate water from the mixture - makes a very
concentrated ammonium nitrate product
Ammonium nitrate reaction - in the lab - ✔✔✔ ANSWER > Carried out on a
much smaller scale by titration & crystallisation
Reactants are at a much lower concentration than in industry - less heat is
produced & it's safer for a person to carry out
After the titration, the mixture is then crystallised to give pure ammonium
nitrate crystals - crystallisation isn't used in industry as it's very slow
Are alcohols flammable? - ✔✔✔ ANSWER > Yes
Are alkanes or alkenes more reactive? - ✔✔✔ ANSWER > Alkenes - their
double bond can open up to allow the carbon atoms to form more bonds
Are alkanes saturated or unsaturated? - ✔✔✔ ANSWER > They are saturated
- each carbon atoms forms four single covalent bonds
Are alkenes saturated or unsaturated? - ✔✔✔ ANSWER > They are
unsaturated Are all reactions endothermic in one direction & exothermic in
the other? - ✔✔✔
ANSWER > Yes
Are reversible reactions endothermic or exothermic? - ✔✔✔ ANSWER > They
can be both - if the reaction is endothermic in one direction, it will be
exothermic in the other
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,The energy transferred from the surroundings by the endothermic reaction is
equal to the energy transferred to the surroundings during the exothermic
reaction
At a lower temperature, will the yield of ammonia be smaller or greater? -
✔✔✔ ANSWER > Greater - the forward reaction of the Haber process is
exothermic, therefore increasing the temperature will move the equilibrium
the wrong way
Can iron rust with just water? - ✔✔✔ ANSWER > No - in order to rust, iron
needs to be exposed to water & oxygen
Catalytic cracking method - ✔✔✔ ANSWER > 1) Heat long chain hydrocarbons
to vaporise them
2) Pass the vapour over a hot powdered aluminium oxide catalyst
3) The long-chain hydrocarbon molecules split apart on the surface of the
specks of catalyst
Changes to Concentration - ✔✔✔ ANSWER > Changing the concentration will
cause the system to bring itself back to equilibrium
Increasing the concentration causes the system to decrease it by making
more products
Decreasing the concentration causes the system to increase it by reducing the
amount of reactants
Changes to Pressure - ✔✔✔ ANSWER > Only affects an equilibrium involving
gases
Increasing the pressure will cause the equilibrium to try & reduce it, thus
making it move in the direction where there are fewer gas molecules
Decreasing the pressure will cause the equilibrium to try & increase it, thus
making it move in the direction where there are more gas molecules
Changes to Temperature - ✔✔✔ ANSWER > 1) If you decrease the
temperature, the equilibrium will move in the exothermic direction to
produce more heat, therefore you'll get more products for the exothermic
reaction and fewer products for the endothermic reaction
3|Page
, 2) If you increase the temperature, the equilibrium will move in the
endothermic direction to try & decrease it, therefore, you'll get more products
for the endothermic reaction and fewer products for the exothermic reaction
Chromatography - Mobile Phase - ✔✔✔ ANSWER > Where the molecules can
move - this is always a liquid or a gas
Chromatography - Stationary Phase - ✔✔✔ ANSWER > Where the molecules
can't move - this can be a solid or a really thick liquid
Complete combustion of alcohol - ✔✔✔ ANSWER > Alcohol + oxygen -->
carbon dioxide + water
Complete combustion of hydrocarbons formula - ✔✔✔ ANSWER >
Hydrocarbon + oxygen --> carbon dioxide + water (+ energy)
Composite properties - Carbon fibres - ✔✔✔ ANSWER > Have a polymer
matrix
The reinforcement is either made from long chains of carbon atoms bonded
together (carbon fibres) or from carbon nanotubes
Very strong & light
Used in aerospace & sports car manufacturing
Composite properties - Concrete - ✔✔✔ ANSWER > Made from aggregate (a
mixture of sand & gravel) embedded in cement
Very strong
Used as a building material
Composite properties - Fibreglass - ✔✔✔ ANSWER > Consists of fibres of glass
embedded in a matrix made of polymer (plastic)
Has a low density - like plastic
Very strong - like glass
Used for things like skis, boats & surfboards
Composite properties - Wood - ✔✔✔ ANSWER > Natural composite of cellulose
fibres held together by an organic polymer matrix
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CHEMISTRY – PAPER 2
ACTUAL EXAM WITH COMPLETE
SOLUTIONS RATED A
Addition polymerisation - ✔✔✔ ANSWER > Only one monomer type
Only one product formed
C=C bond in monomer
Advantage of phytomining & bioleaching - ✔✔✔ ANSWER > They have a much
smaller impact on the environment
Advantages of using machines for tests - ✔✔✔ ANSWER > 1) Very sensitive -
they can detect even the tiniest amounts of substances
2) Very fast - tests can be automated
3) Very accurate
Alloys - Aluminium alloys - ✔✔✔ ANSWER > Aluminium has a low density -
important property in aircraft manufacture
Pure aluminium is too soft aeroplanes - allowed with small amounts of other
metals to make it stronger
Alloys - Brass - ✔✔✔ ANSWER > Copper + Zinc
More malleable than bronze
Used in situations where lower friction is required e.g. water taps & door
fittings Alloys - Bronze - ✔✔✔ ANSWER > Copper + Tin
Harder than copper
Used to make medals, decorative ornaments & statues
Alloys - Gold alloys - ✔✔✔ ANSWER > Pure gold is very soft - metals such as
zinc, copper & silver are used to harden it
Used to make jewellery
1|Page
,Aluminium rusting - ✔✔✔ ANSWER > Aluminium corrodes when exposed to air
Aluminium objects aren't completely destroyed by corrosion - the aluminium
oxide that forms doesn't flake away, but it forms a nice protective layer that
sticks firmly to the aluminium below and stops any further reaction taking
place
Ammonium nitrate formula - ✔✔✔ ANSWER > Ammonia + Nitric Acid -->
Ammonium Nitrate
NH3(aq) + HNO3(aq) --> NH4NO3(aq)
Ammonium nitrate reaction - in industry - ✔✔✔ ANSWER > Carried out in
giant vats at high concentrations -results in a very exothermic reaction
Heat released is used to evaporate water from the mixture - makes a very
concentrated ammonium nitrate product
Ammonium nitrate reaction - in the lab - ✔✔✔ ANSWER > Carried out on a
much smaller scale by titration & crystallisation
Reactants are at a much lower concentration than in industry - less heat is
produced & it's safer for a person to carry out
After the titration, the mixture is then crystallised to give pure ammonium
nitrate crystals - crystallisation isn't used in industry as it's very slow
Are alcohols flammable? - ✔✔✔ ANSWER > Yes
Are alkanes or alkenes more reactive? - ✔✔✔ ANSWER > Alkenes - their
double bond can open up to allow the carbon atoms to form more bonds
Are alkanes saturated or unsaturated? - ✔✔✔ ANSWER > They are saturated
- each carbon atoms forms four single covalent bonds
Are alkenes saturated or unsaturated? - ✔✔✔ ANSWER > They are
unsaturated Are all reactions endothermic in one direction & exothermic in
the other? - ✔✔✔
ANSWER > Yes
Are reversible reactions endothermic or exothermic? - ✔✔✔ ANSWER > They
can be both - if the reaction is endothermic in one direction, it will be
exothermic in the other
2|Page
,The energy transferred from the surroundings by the endothermic reaction is
equal to the energy transferred to the surroundings during the exothermic
reaction
At a lower temperature, will the yield of ammonia be smaller or greater? -
✔✔✔ ANSWER > Greater - the forward reaction of the Haber process is
exothermic, therefore increasing the temperature will move the equilibrium
the wrong way
Can iron rust with just water? - ✔✔✔ ANSWER > No - in order to rust, iron
needs to be exposed to water & oxygen
Catalytic cracking method - ✔✔✔ ANSWER > 1) Heat long chain hydrocarbons
to vaporise them
2) Pass the vapour over a hot powdered aluminium oxide catalyst
3) The long-chain hydrocarbon molecules split apart on the surface of the
specks of catalyst
Changes to Concentration - ✔✔✔ ANSWER > Changing the concentration will
cause the system to bring itself back to equilibrium
Increasing the concentration causes the system to decrease it by making
more products
Decreasing the concentration causes the system to increase it by reducing the
amount of reactants
Changes to Pressure - ✔✔✔ ANSWER > Only affects an equilibrium involving
gases
Increasing the pressure will cause the equilibrium to try & reduce it, thus
making it move in the direction where there are fewer gas molecules
Decreasing the pressure will cause the equilibrium to try & increase it, thus
making it move in the direction where there are more gas molecules
Changes to Temperature - ✔✔✔ ANSWER > 1) If you decrease the
temperature, the equilibrium will move in the exothermic direction to
produce more heat, therefore you'll get more products for the exothermic
reaction and fewer products for the endothermic reaction
3|Page
, 2) If you increase the temperature, the equilibrium will move in the
endothermic direction to try & decrease it, therefore, you'll get more products
for the endothermic reaction and fewer products for the exothermic reaction
Chromatography - Mobile Phase - ✔✔✔ ANSWER > Where the molecules can
move - this is always a liquid or a gas
Chromatography - Stationary Phase - ✔✔✔ ANSWER > Where the molecules
can't move - this can be a solid or a really thick liquid
Complete combustion of alcohol - ✔✔✔ ANSWER > Alcohol + oxygen -->
carbon dioxide + water
Complete combustion of hydrocarbons formula - ✔✔✔ ANSWER >
Hydrocarbon + oxygen --> carbon dioxide + water (+ energy)
Composite properties - Carbon fibres - ✔✔✔ ANSWER > Have a polymer
matrix
The reinforcement is either made from long chains of carbon atoms bonded
together (carbon fibres) or from carbon nanotubes
Very strong & light
Used in aerospace & sports car manufacturing
Composite properties - Concrete - ✔✔✔ ANSWER > Made from aggregate (a
mixture of sand & gravel) embedded in cement
Very strong
Used as a building material
Composite properties - Fibreglass - ✔✔✔ ANSWER > Consists of fibres of glass
embedded in a matrix made of polymer (plastic)
Has a low density - like plastic
Very strong - like glass
Used for things like skis, boats & surfboards
Composite properties - Wood - ✔✔✔ ANSWER > Natural composite of cellulose
fibres held together by an organic polymer matrix
4|Page
