# Ethene is produced by cracking long-chain hydrocarbons. Ethene can then be used to make poly(ethene). Describe how poly(ethene) is formed from ethene and explain why ethene, rather than ethane, must be used as the monomer.

> AQA A-Level Chemistry (7405) — 3.3.11 Amines (A-Level only) · Describe and Explain · 5 marks

## Mark scheme (5 marks)

1. Many ethene molecules (monomers) join together to form poly(ethene) (the polymer)
2. The process is called addition polymerisation
3. No other product/no small molecule is lost/released during the reaction
4. Ethene is unsaturated / has a carbon–carbon double bond
5. Ethane is saturated / has no double bond, so it cannot open up to link with other monomers / cannot undergo addition polymerisation

## Key terms

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

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Source: [GradeNine](https://www.gradenine.co.uk/q/ethene-is-produced-by-cracking-long-chain-7c145f53) · Published by Druglandscape Ltd.