# Methanol (CH₃OH) and 1-chloropropane (CH₃CH₂CH₂Cl) are examples of an alcohol and a halogenoalkane respectively. Explain the similarities and differences between the structures of alcohols and halogenoalkanes, and describe what happens when a halogenoalkane undergoes hydrolysis.

> WJEC A-Level Chemistry (Wales) — 3.3 Alcohols and halogenoalkanes · Explain · 5 marks

> Alcohols contain a hydroxyl group (–OH) bonded to a carbon chain. Halogenoalkanes are formed when the hydroxyl group of an alcohol is replaced by a halogen atom.

## Mark scheme (5 marks)

1. Both alcohols and halogenoalkanes have a carbon chain / hydrocarbon backbone
2. Alcohols contain a hydroxyl group (–OH) attached to the carbon chain
3. Halogenoalkanes contain a halogen atom (F, Cl, Br or I) in place of the hydroxyl group
4. During hydrolysis of a halogenoalkane, the halogen atom is replaced by a hydroxyl group (–OH)
5. Water (or aqueous alkali / hydroxide ions) acts as the reagent in hydrolysis, breaking the C–halogen bond

## Key terms

- [halogenoalkane](https://www.gradenine.co.uk/glossary/halogenoalkane)
- [hydrolysis](https://www.gradenine.co.uk/glossary/hydrolysis)

## Related

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Source: [GradeNine](https://www.gradenine.co.uk/q/methanol-ch-oh-and-1-chloropropane-ch-ch-ch-cl-are-fef70dfb) · Published by Druglandscape Ltd.