# Explain why the pressure of a fixed mass of gas increases when its temperature is raised at constant volume.

> Cambridge International IGCSE Physics (0625) — 2.1 Kinetic particle model of matter · Explain · 4 marks

## Mark scheme (4 marks)

1. Higher temperature means greater average kinetic energy of the molecules
2. Molecules move faster / with greater speed
3. Molecules collide with the walls of the container more frequently
4. Each collision exerts a greater force on the walls / molecules rebound with greater change in momentum

## Key terms

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

## Related

- [Revision notes for Cambridge International IGCSE Physics (0625)](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-the-pressure-of-a-3f99837b) · Published by Druglandscape Ltd.