# A metal perfume bottle contains liquid perfume and perfume vapour above the liquid. The bottle is sealed. Explain, using kinetic theory, why the pressure inside the bottle increases when the bottle is left in a warm car on a sunny day.

> Eduqas A-Level Physics — 3.3 Kinetic theory · Explain · 5 marks

## Mark scheme (5 marks)

1. The particles of the perfume vapour gain kinetic energy / move faster when temperature increases
2. The particles collide with the walls of the bottle more frequently
3. The particles hit the walls with greater force
4. The volume of the sealed bottle stays constant / fixed
5. More frequent and more forceful collisions per unit area on the walls result in greater pressure

## Key terms

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

## Related

- [Revision notes for Eduqas A-Level Physics](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-metal-perfume-bottle-contains-liquid-6ac70313) · Published by Druglandscape Ltd.