Coding for branched chains

3 marks · Easy

The table below shows structures of different side chains found in organic molecules. Study the table and answer the questions.

(a)

Side chain structures and codes.
Side chain	Structure	Code
A
B

Complete the 'Code' column for both A and B.

[2 marks]

(b)

Explain how you identified the codes for the side chains.

[1 mark]

Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.

Show answer

(a) A: methyl; B: ethyl

(b) By counting the number of carbon atoms in each side chain and using 'meth' for one and 'eth' for two.

Show mark scheme and worked solution

Marking points

B1 (a) · 1 mark · Correctly completes A as methyl.

B2 (a) · 1 mark · Correctly completes B as ethyl.

B3 (b) · 1 mark · Explains identification based on carbon atom count and coding rules.

Worked solution

Side chain	Structure	Code
A		methyl
B		ethyl

A has one carbon (meth) and B has two (eth), so their codes are methyl and ethyl.