AQA A Level Chemistry – Organic and Physical Chemistry Marking Scheme | Updated Fall Semester 2025/2026 Complete Study Resource | 290+ Verified Exam Answers with Mark Scheme Explanations | Comprehensive Guide for A Level Chemistry Paper 2 & Paper 3 Revisi

AQA A Level Chemistry – Organic and Physical
Chemistry Marking Scheme | Updated Fall
Semester 2025/2026 Complete Study Resource |
290+ Verified Exam Answers with Mark Scheme
Explanations | Comprehensive Guide for A Level
Chemistry Paper 2 & Paper 3 Revision and Exam
Preparation

Question 1
What functional group is characteristic of alcohols?
Correct Answer: Hydroxyl group (-OH)
Rationale: Alcohols contain a hydroxyl group attached to a carbon atom.


Question 2
What is produced from the complete combustion of propane (C3H8)?
Correct Answer: Carbon dioxide and water
Rationale: Complete combustion yields CO2 and H2O when sufficient oxygen is
available.


Question 3
Which reagent is used to test for unsaturation in organic compounds?
Correct Answer: Bromine solution
Rationale: Bromine solution changes color in the presence of double bonds.


Question 4
What type of reaction occurs when an alcohol is converted to an alkene?
Correct Answer: Dehydration
Rationale: Dehydration involves the removal of water to form an alkene.


Question 5
Which species acts as a nucleophile?
Correct Answer: Hydroxide ion (OH-)
Rationale: Nucleophiles donate electron pairs; OH- can do this in reactions.

,Question 6
What is the main product when an alkene reacts with hydrogen bromide (HBr)?
Correct Answer: Bromoalkane
Rationale: Electrophilic addition converts the alkene to a bromoalkane.


Question 7
What characterizes a primary alcohol?
Correct Answer: The -OH group is attached to a carbon bonded to one other carbon.
Rationale: Primary alcohols have the hydroxyl group on a carbon bonded to one other
carbon.


Question 8
In which reaction does an aldehyde become a carboxylic acid?
Correct Answer: Heating with potassium dichromate (VI) in acidic conditions
Rationale: Oxidation transforms aldehydes to carboxylic acids.


Question 9
What is the IUPAC name for CH3-CH2-CHO?
Correct Answer: Propanal
Rationale: The compound is a three-carbon aldehyde, named propanal.


Question 10
Which of the following is a strong acid?
Correct Answer: Sulfuric acid (H2SO4)
Rationale: Sulfuric acid fully dissociates in water, unlike the others.


Question 11
What is produced from the hydrolysis of a halogenoalkane?
Correct Answer: Alcohol
Rationale: Hydrolysis replaces the halogen with a hydroxyl group.

,Question 12
Which statement about electrophilic addition reactions is true?
Correct Answer: Electrophiles are attracted to areas of high electron density.
Rationale: Electrophiles seek out electrons, such as those in double bonds.


Question 13
What is the role of a catalyst in a chemical reaction?
Correct Answer: To increase the rate of reaction without being consumed.
Rationale: Catalysts lower activation energy and are not used up.


Question 14
Which compound is a ketone?
Correct Answer: Propan-2-one
Rationale: Propan-2-one contains a carbonyl group between two carbons.


Question 15
What forms when an alcohol reacts with a carboxylic acid in acidic conditions?
Correct Answer: Ester
Rationale: The reaction produces an ester through esterification.


Question 16
What characterizes a secondary alcohol?
Correct Answer: The -OH group is attached to a carbon bonded to two other carbons.
Rationale: Secondary alcohols have the hydroxyl group on a carbon bonded to two
other carbons.


Question 17
What is the product of alcohol oxidation?
Correct Answer: Ketone or aldehyde
Rationale: Primary alcohols oxidize to aldehydes; secondary alcohols to ketones.


Question 18

, What is the IUPAC name for CH3-CO-CH2-CH3?
Correct Answer: Butan-2-one
Rationale: This is a four-carbon ketone, named butan-2-one.


Question 19
Which reaction involves a nucleophile attacking a haloalkane?
Correct Answer: Nucleophilic substitution
Rationale: Nucleophiles replace the halogen in haloalkanes.


Question 20
What is the effect of increasing temperature on reaction rate?
Correct Answer: It generally increases the rate of reaction.
Rationale: Higher temperatures provide more energy for effective collisions.


Question 21
Which compounds can undergo elimination reactions?
Correct Answer: Haloalkanes
Rationale: Haloalkanes can lose a halogen and form an alkene when treated with a
strong base.


Question 22
What is produced when an alkene reacts with sulfuric acid?
Correct Answer: Alkyl hydrogensulfate
Rationale: The alkene reacts to form an alkyl hydrogensulfate intermediate.


Question 23
What is the significance of using a desiccant in reactions?
Correct Answer: To remove water from a substance.
Rationale: Desiccants absorb moisture, aiding in drying processes.


Question 24
What is the primary product of the hydrolysis of an ester?