Propanol can be produced from propene. Describe how propanol is formed from propene, and state the functional group present in propanol.

Pearson Edexcel International GCSE Chemistry (4CH1) — 4.5 Alcohols · Describe · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Propanol is a member of the alcohols homologous series and can be manufactured industrially from propene.

Model answer (4 marks)

Propene reacts with steam in the presence of a phosphoric acid catalyst. The double bond of propene undergoes an addition reaction, giving a larger single molecule – 1‑propanol. The functional group present in propanol is the hydroxyl group –OH.

Examiner tips

Use the term ‘addition reaction’ and mention the catalyst; this shows understanding of the mechanism.
State the functional group explicitly – the –OH (hydroxyl) group – to earn the mark for the second part.

Common mistakes

Confusing the reaction with a substitution or elimination reaction.
Omitting the catalyst or the fact that it is an addition reaction.
Not naming the functional group as –OH (hydroxyl).

Mark scheme (4 marks)

Propene reacts with steam (in an addition reaction)
A phosphoric acid catalyst is used
This is an addition reaction (a larger single molecule is formed from two smaller molecules)
The functional group in propanol is –OH (hydroxyl group)

Key terms in this question

functional group