# Explain why gases are much more compressible than liquids.

> IB DP Chemistry Higher Level (2023 syllabus) — S1.1 Introduction to the particulate nature of matter · Explain · 4 marks

## Mark scheme (4 marks)

1. In a gas, particles are far apart / separated by large distances compared to the size of the particles themselves.
2. Applying pressure forces the gas particles closer together / reduces the space between particles, so the volume decreases.
3. In a liquid, particles are already very close together / touching / in contact, with negligible space between them.
4. Therefore, there is little/no space available to reduce between liquid particles, so the volume cannot decrease significantly under pressure.

## Key terms

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

## Related

- [Revision notes for IB DP Chemistry Higher Level (2023 syllabus)](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)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/explain-why-gases-are-much-more-db0f9b56) · Published by Druglandscape Ltd.