# Ethene can undergo addition reactions with several different reagents. Describe what happens when ethene reacts with steam, including the conditions required and the name of the product formed.

> Edexcel GCSE Chemistry (1CH0) — 10.2 Alkenes (Chem only) · Describe · 4 marks

## Mark scheme (4 marks)

1. High temperature/pressure is required as a condition
2. A catalyst (phosphoric acid / H3PO4) is required
3. The C=C double bond in ethene breaks / opens up (addition reaction)
4. The product formed is ethanol

## Key terms

- [addition reaction](https://www.gradenine.co.uk/glossary/addition-reaction)

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Source: [GradeNine](https://www.gradenine.co.uk/q/ethene-can-undergo-addition-reactions-with-d489afd2) · Published by Druglandscape Ltd.