OCR A-Level Chemistry Synthesis and analytical techniques (02), June 2019: Question 15

1 mark · Medium difficulty · Multiple Choice

Identify the functional groups present in a given complex organic molecule used to treat influenza from a multiple-choice list.

Practise this question

Question

Multiple choice question 15 showing the chemical structure of an antiviral compound containing ester, amide, amine, ether and alkene groups. Below the structure, three numbered statements list functional groups: 1 Ester, 2 Secondary amide, 3 Ketone. Four options A, B, C, D are provided, representing combinations of these statements.
Question text

15 The structure of a compound used to treat influenza is shown below.

O

O

O

HN

NH2

O

Which functional group(s) is/are in a molecule of the compound?

1 Ester

2 Secondary amide

3 Ketone

A 1, 2 and 3

B Only 1 and 2

C Only 2 and 3

D Only 1

Your answer

[1]

Mark scheme

Show the mark scheme Mark scheme for question 15 indicating the correct answer is B, worth 1 mark.

15 B 1 AO1.2

Total 15

SECTION B

How to answer it

Identifying Functional Groups in Complex Organic Molecules

What this question tests

This question assesses your ability to recognise and distinguish between various organic functional groups (esters, secondary amides, and ketones) within a complex, multi-functional drug molecule (Oseltamivir / Tamiflu). It tests AO1 knowledge and understanding of structural chemistry definitions.

Question 15: Functional Group Analysis

Multiple Choice Question (1 Mark)

✅ Correct Answer: B (Only 1 and 2)

Statement 1 (Ester) and Statement 2 (Secondary amide) are present in the molecule, while Statement 3 (Ketone) is absent.

💡 Key Knowledge

  • Ester group: Found on the right side ( -COO- or -COOCH₂CH₃ ).
  • Secondary amide: Found branching off the ring ( -NH-CO-CH₃ ), where the nitrogen is bonded to one carbon chain and one carbonyl carbon.
  • Ketone check: The C=O double bonds present are part of an ester and an amide, not an isolated ketone (which requires a carbonyl carbon bonded to two other carbons).

🧠 Exam Technique

Scan the molecule methodically, crossing off functional groups as you identify them against the list provided. Do not let complex skeletal structures intimidate you—break them down piece by piece starting from terminal groups.

❌ Common Errors

Students frequently misidentify the carbonyl group in the amide or ester as a ketone because they spot a C=O double bond without checking what atoms the adjacent carbon is bonded to.

Mark Scheme Allocation: 1 mark for selecting option B (AO1.2).

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 2019. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.