AQA GCSE Combined Science Trilogy - Chemistry - Paper 2
1. What is a substance that is composed of only one element, compound, or substance not mixed with
another substance?
Answer: Pure substance.
2. How can mixtures be separated?
Answer: Physical processes such as filtration, simple distillation, fractional distillation, and
chromatography can be used to separate mixtures.
3. What is simple distillation used for?
Answer: Simple distillation involves evaporating water and condensing it in a separate container to
separate a mixture.
4. What is fractional distillation used for?
Answer: Fractional distillation is used to separate liquids with different boiling points by evaporating
them and condensing them in separate containers.
5. How does filtration work?
Answer: Filtration involves screening and sieving to remove solids from a mixture.
6. What is chromatography used for?
Answer: Chromatography is used to separate pigments by using a solvent to identify them.
7. How does crystallization work?
,Answer: Crystallization involves evaporating a solution to a small volume and leaving it to cool to form
crystals.
8. What distinguishes a mixture from a chemically bonded substance?
Answer: A mixture is made from different substances that are not chemically bonded, whereas
chemically bonded substances have atoms or molecules bonded together.
9. How is a formulation made?
Answer: A formulation is made by mixing components in carefully measured amounts to create a
specific mixture designed for a particular use.
10. How does paper chromatography work?
Answer: In paper chromatography, the solvent moves through the paper, carrying different compounds
to different distances depending on their attraction to the paper and solvent.
11. What is the Rf value in chromatography?
Answer: The Rf value is the distance moved by the compound divided by the distance moved by the
solvent.
12. What is the result of running a pure compound through chromatography?
Answer: In chromatography, a pure compound produces a single spot in all solvents.
13. How does chlorine react with litmus paper?
, Answer: Chlorine turns damp blue litmus paper red and then bleaches it white.
14. How does oxygen gas react with a glowing splint?
Answer: Oxygen gas test makes a glowing splint relight.
15. What sound does hydrogen gas make when tested?
Answer: Hydrogen gas test makes a squeaky pop sound.
16. How does carbon dioxide gas react with limewater?
Answer: Carbon dioxide gas test makes limewater go cloudy.
17. What basic human needs do natural resources provide?
Answer: Natural resources provide humans with warmth, shelter, food, and transport.
18. What are some examples of natural resources along with agriculture that give us food, timber,
clothing, and fuels?
Answer: Natural resources along with agriculture give us food, timber, clothing, and fuels.
19. What kind of resources involve processes to make energy and materials?
Answer: Finite resources involve processes to make energy and materials.
20. What does finite mean in the context of resources?
1. What is a substance that is composed of only one element, compound, or substance not mixed with
another substance?
Answer: Pure substance.
2. How can mixtures be separated?
Answer: Physical processes such as filtration, simple distillation, fractional distillation, and
chromatography can be used to separate mixtures.
3. What is simple distillation used for?
Answer: Simple distillation involves evaporating water and condensing it in a separate container to
separate a mixture.
4. What is fractional distillation used for?
Answer: Fractional distillation is used to separate liquids with different boiling points by evaporating
them and condensing them in separate containers.
5. How does filtration work?
Answer: Filtration involves screening and sieving to remove solids from a mixture.
6. What is chromatography used for?
Answer: Chromatography is used to separate pigments by using a solvent to identify them.
7. How does crystallization work?
,Answer: Crystallization involves evaporating a solution to a small volume and leaving it to cool to form
crystals.
8. What distinguishes a mixture from a chemically bonded substance?
Answer: A mixture is made from different substances that are not chemically bonded, whereas
chemically bonded substances have atoms or molecules bonded together.
9. How is a formulation made?
Answer: A formulation is made by mixing components in carefully measured amounts to create a
specific mixture designed for a particular use.
10. How does paper chromatography work?
Answer: In paper chromatography, the solvent moves through the paper, carrying different compounds
to different distances depending on their attraction to the paper and solvent.
11. What is the Rf value in chromatography?
Answer: The Rf value is the distance moved by the compound divided by the distance moved by the
solvent.
12. What is the result of running a pure compound through chromatography?
Answer: In chromatography, a pure compound produces a single spot in all solvents.
13. How does chlorine react with litmus paper?
, Answer: Chlorine turns damp blue litmus paper red and then bleaches it white.
14. How does oxygen gas react with a glowing splint?
Answer: Oxygen gas test makes a glowing splint relight.
15. What sound does hydrogen gas make when tested?
Answer: Hydrogen gas test makes a squeaky pop sound.
16. How does carbon dioxide gas react with limewater?
Answer: Carbon dioxide gas test makes limewater go cloudy.
17. What basic human needs do natural resources provide?
Answer: Natural resources provide humans with warmth, shelter, food, and transport.
18. What are some examples of natural resources along with agriculture that give us food, timber,
clothing, and fuels?
Answer: Natural resources along with agriculture give us food, timber, clothing, and fuels.
19. What kind of resources involve processes to make energy and materials?
Answer: Finite resources involve processes to make energy and materials.
20. What does finite mean in the context of resources?
