OCR A-Level Chemistry Synthesis and analytical techniques (02), June 2023: Question 4

1 mark · Easy difficulty · Multiple Choice

Identify the functional groups present in the structure of paracetamol from a multiple-choice list.

Practise this question

Question

Multiple-choice question 4 shows the chemical structure of paracetamol, which consists of a benzene ring substituted with an OH group and an NHCOCH3 (amide) group. Below the structure, students are asked to choose the correct combination of functional groups present from four options: A (alcohol, amide), B (alcohol, arene, ketone, amine), C (phenol, amide), and D (phenol, ketone, amine).
Question text

4 The structure of the painkiller paracetamol is shown below.

OH

O

N

H

Paracetamol

Which functional groups are present in paracetamol?

A alcohol, amide

B alcohol, arene, ketone, amine

C phenol, amide

D phenol, ketone, amine

Your answer

[1]

Mark scheme

Show the mark scheme The mark scheme shows that the correct answer for question 4 is option C.

4 C 1 AO1.2

How to answer it

Identifying Functional Groups in Paracetamol

What this question tests

This question assesses your ability to recognize and distinguish between key organic functional groups from structural formulae, specifically knowing the difference between aliphatic alcohols/amines versus phenols and amides.

Question Multiple Choice Analysis

Question 4

✅ Correct Answer: C (phenol, amide)

The structure contains a hydroxyl group directly attached to a benzene ring ( phenol ) and a nitrogen atom bonded directly to a carbonyl carbon ( amide ).

💡 Key Knowledge

  • Phenol vs Alcohol: An -OH group attached directly to an aromatic ring behaves differently and is classified specifically as a phenol, not an aliphatic alcohol.
  • Amide vs Amine/Ketone: The group -NH-C(=O)- is a single functional group known as a secondary amide, not a separate amine and ketone.

🧠 Exam Technique

Scan complex pharmaceutical molecules systematically by looking at sub-structures: check aromatic rings for substituents ( -OH ), and inspect linking chains for heteroatoms combined with carbonyls ( -CONH- ).

❌ Common Errors

  • Choosing A by failing to recognize that an -OH on a benzene ring is a phenol, not a simple alcohol.
  • Choosing B or D by splitting the amide linkage ( -NH-C=O ) into isolated "amine" and "ketone" groups.
Mark Scheme Allocation: 1 mark awarded for selecting option C (AO1.2 - Demonstrating knowledge and understanding of organic functional groups).

Topics

Module 4: Core organic chemistry · Module 6: Organic chemistry and analysis · 4.1 Basic concepts and hydrocarbons · 6.1 Aromatic compounds, carbonyls and acids · 6.2 Nitrogen compounds, polymers and synthesis

Question and mark scheme from the OCR A-Level Chemistry examination, Synthesis and analytical techniques (02), June 2023. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.