# Ethanol can be used as a fuel and as a solvent. Describe how ethanol is produced by the hydration of ethene, and explain two reasons why this method may be preferred over fermentation for industrial fuel production.

> AQA A-Level Chemistry (7405) — 3.3.5 Alcohols · Describe · 5 marks

## Mark scheme (5 marks)

1. Ethene reacts with steam (water) to produce ethanol
2. A catalyst (phosphoric acid) is used
3. High temperature and/or high pressure are required
4. Hydration produces a purer / higher quality ethanol compared to fermentation (or continuous process so more efficient)
5. Hydration uses ethene (a non-renewable petrochemical / from crude oil) whereas fermentation uses renewable sugar/glucose; so hydration gives a faster / more controllable rate of production

## Key terms

- [hydration](https://www.gradenine.co.uk/glossary/hydration)
- [ethene](https://www.gradenine.co.uk/glossary/ethene)
- [fermentation](https://www.gradenine.co.uk/glossary/fermentation)
- [ethanol](https://www.gradenine.co.uk/glossary/ethanol)

## Related

- [Revision notes for AQA A-Level Chemistry (7405)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/ethanol-can-be-used-as-a-bcafb3a9) · Published by Druglandscape Ltd.