# A sealed rigid container holds a fixed mass of gas. The temperature of the gas is increased at constant volume. Explain why the pressure of the gas increases.

> Pearson Edexcel International GCSE Physics (4PH1) — 5.3 Ideal gas molecules · Explain · 4 marks

## Mark scheme (4 marks)

1. Gas molecules move faster (at higher temperature)
2. Molecules collide with the walls more frequently
3. Molecules collide with the walls harder / with greater force (greater change in momentum per collision)
4. Pressure is the perpendicular force per unit area on the container walls, so greater force from collisions means greater pressure (volume/area unchanged)

## Key terms

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

## Related

- [Revision notes for Pearson Edexcel International GCSE Physics (4PH1)](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/a-sealed-rigid-container-holds-a-9c46196a) · Published by Druglandscape Ltd.