# Explain why a substance in the gaseous state has a much lower density than the same substance in the liquid state.

> Edexcel GCSE Chemistry (1CH0) — 1.1 States of matter · Explain · 4 marks

## Mark scheme (4 marks)

1. In a gas, particles are far apart / have large gaps between them
2. In a liquid, particles are close together / touching / very little space between them
3. The same mass / number of particles occupies a much greater volume in the gas than in the liquid
4. Density = mass ÷ volume, so a larger volume for the same mass means a lower density for the gas

## Key terms

- [density](https://www.gradenine.co.uk/glossary/density)
- [gaseous state](https://www.gradenine.co.uk/glossary/gaseous-state)
- [liquid state](https://www.gradenine.co.uk/glossary/liquid-state)

## Related

- [Revision notes for Edexcel GCSE Chemistry (1CH0)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" 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/explain-why-a-substance-in-the-65ccaecf) · Published by Druglandscape Ltd.