# Ethene (C₂H₄) can be converted into poly(ethene) by a process called addition polymerisation. Describe what happens during addition polymerisation and explain why the product, poly(ethene), has different properties to ethene.

> Eduqas GCSE Chemistry — C7 Organic chemistry · Describe and Explain · 4 marks

## Mark scheme (4 marks)

1. Many/thousands of ethene monomers join together (to form a polymer)
2. The double bond in ethene opens/breaks to allow the monomers to join
3. Poly(ethene) has a very large/high molecular mass compared to ethene
4. The larger molecules in poly(ethene) mean it is a solid at room temperature / has a higher melting point / stronger intermolecular forces, whereas ethene is a gas

## Key terms

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

## Related

- [Revision notes for Eduqas GCSE Chemistry](https://www.gradenine.co.uk/learn)
- [How to answer "Describe and Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/ethene-c-h-can-be-converted-into-26bcba2c) · Published by Druglandscape Ltd.