# Ethanol can be converted into chloroethane by reacting it with phosphorus pentachloride. Explain why chloroethane is classified as a halogenoalkane and describe two chemical properties of halogenoalkanes that differ from those of alcohols.

> Eduqas A-Level Chemistry — 3.3 Alcohols and halogenoalkanes · Explain · 5 marks

> Ethanol has the molecular formula C₂H₅OH. Chloroethane has the molecular formula C₂H₅Cl.

## Mark scheme (5 marks)

1. Chloroethane is classified as a halogenoalkane because it contains a halogen atom (chlorine) bonded to a carbon chain / an alkyl group
2. Halogenoalkanes do not contain an –OH (hydroxyl) group, whereas alcohols do
3. Halogenoalkanes do not undergo combustion to produce carbon dioxide and water in the same way as alcohols / alcohols burn completely in excess oxygen to give CO₂ and H₂O whereas halogenoalkanes do not combust cleanly
4. Halogenoalkanes undergo hydrolysis / substitution reactions with water or hydroxide ions to form alcohols, whereas alcohols do not undergo this reaction
5. Halogenoalkanes do not react with sodium / do not produce hydrogen gas when added to sodium, whereas alcohols react with sodium to release hydrogen gas

## Key terms

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

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- [Revision notes for Eduqas A-Level Chemistry](https://www.gradenine.co.uk/learn)
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Source: [GradeNine](https://www.gradenine.co.uk/q/ethanol-can-be-converted-into-chloroethane-0e55f156) · Published by Druglandscape Ltd.