AQA A-level CHEMISTRY 7405/2 Paper 2: Organic and
Physical Chemistry Question Paper and Mark scheme
1. Define functional group.
An atom/group responsible for the characteristic reactions of a molecule.
2. Name the functional group in alcohols.
–OH (hydroxyl group).
3. Name the functional group in carboxylic acids.
–COOH (carboxyl group).
4. Name the functional group in aldehydes.
–CHO.
5. Name the functional group in ketones.
–CO– (carbonyl group within chain).
6. Name the functional group in esters.
–COO–.
7. What is structural isomerism?
Compounds with the same molecular formula but different structural
formulas.
8. What is stereoisomerism?
Compounds with the same structural formula but different spatial
arrangement.
9. Name two types of stereoisomerism.
E/Z isomerism and optical isomerism.
10.What causes E/Z isomerism?
Restricted rotation around a C=C bond.
11.What is the test for alkenes?
Bromine water decolourises.
12.What is the test for carboxylic acids?
Add NaHCO₃; effervescence from CO₂ gas.
13.What is the test for aldehydes?
Tollens’ reagent forms silver mirror.
14.What is the test for ketones?
No reaction with Tollens’ reagent.
15.What is the test for alcohols?
Add acidified potassium dichromate: orange to green (1° or 2° alcohols).
16.How are esters formed?
Alcohol + carboxylic acid ⇌ ester + water (with H₂SO₄ catalyst).
, 17.Name a use of esters.
Perfumes or solvents.
18.What reagent converts alcohols to alkenes?
Concentrated H₂SO₄ (elimination reaction).
19.How do you distinguish between primary and tertiary alcohols?
Oxidation with acidified potassium dichromate – primary oxidizes, tertiary
doesn’t.
21.What is an electrophile?
A species that accepts an electron pair.
22.Give an example of an electrophile.
H⁺, Br₂, NO₂⁺.
23.What is a substitution reaction?
One atom/group is replaced by another.
24.What is an elimination reaction?
A small molecule is removed from a compound.
25.Give the mechanism for hydrolysis of halogenoalkanes.
Nucleophilic substitution.
26.Which halogenoalkane hydrolyses fastest?
Iodoalkanes – weakest C–I bond.
27.What is refluxing?
Heating a mixture with a condenser to prevent loss of volatile substances.
28.What is the reagent to convert alcohols to carboxylic acids?
Acidified potassium dichromate under reflux.
29.What is the reaction of an acyl chloride with water?
RCOCl + H₂O → RCOOH + HCl.
30.What is the reaction of an acyl chloride with alcohol?
RCOCl + ROH → RCOOR + HCl.
31.What is the reaction of an acyl chloride with ammonia?
RCOCl + NH₃ → RCONH₂ + HCl.
32.How are amides made?
From acyl chlorides and ammonia or amines.
33.What is a polyester?
A condensation polymer formed from dicarboxylic acid and diol.
Physical Chemistry Question Paper and Mark scheme
1. Define functional group.
An atom/group responsible for the characteristic reactions of a molecule.
2. Name the functional group in alcohols.
–OH (hydroxyl group).
3. Name the functional group in carboxylic acids.
–COOH (carboxyl group).
4. Name the functional group in aldehydes.
–CHO.
5. Name the functional group in ketones.
–CO– (carbonyl group within chain).
6. Name the functional group in esters.
–COO–.
7. What is structural isomerism?
Compounds with the same molecular formula but different structural
formulas.
8. What is stereoisomerism?
Compounds with the same structural formula but different spatial
arrangement.
9. Name two types of stereoisomerism.
E/Z isomerism and optical isomerism.
10.What causes E/Z isomerism?
Restricted rotation around a C=C bond.
11.What is the test for alkenes?
Bromine water decolourises.
12.What is the test for carboxylic acids?
Add NaHCO₃; effervescence from CO₂ gas.
13.What is the test for aldehydes?
Tollens’ reagent forms silver mirror.
14.What is the test for ketones?
No reaction with Tollens’ reagent.
15.What is the test for alcohols?
Add acidified potassium dichromate: orange to green (1° or 2° alcohols).
16.How are esters formed?
Alcohol + carboxylic acid ⇌ ester + water (with H₂SO₄ catalyst).
, 17.Name a use of esters.
Perfumes or solvents.
18.What reagent converts alcohols to alkenes?
Concentrated H₂SO₄ (elimination reaction).
19.How do you distinguish between primary and tertiary alcohols?
Oxidation with acidified potassium dichromate – primary oxidizes, tertiary
doesn’t.
21.What is an electrophile?
A species that accepts an electron pair.
22.Give an example of an electrophile.
H⁺, Br₂, NO₂⁺.
23.What is a substitution reaction?
One atom/group is replaced by another.
24.What is an elimination reaction?
A small molecule is removed from a compound.
25.Give the mechanism for hydrolysis of halogenoalkanes.
Nucleophilic substitution.
26.Which halogenoalkane hydrolyses fastest?
Iodoalkanes – weakest C–I bond.
27.What is refluxing?
Heating a mixture with a condenser to prevent loss of volatile substances.
28.What is the reagent to convert alcohols to carboxylic acids?
Acidified potassium dichromate under reflux.
29.What is the reaction of an acyl chloride with water?
RCOCl + H₂O → RCOOH + HCl.
30.What is the reaction of an acyl chloride with alcohol?
RCOCl + ROH → RCOOR + HCl.
31.What is the reaction of an acyl chloride with ammonia?
RCOCl + NH₃ → RCONH₂ + HCl.
32.How are amides made?
From acyl chlorides and ammonia or amines.
33.What is a polyester?
A condensation polymer formed from dicarboxylic acid and diol.
