# Describe the differences between boiling and evaporation. In your answer, refer to where each process occurs and the temperatures at which each process can take place.

> Cambridge International IGCSE Physics (0625) — 2.2 Thermal properties and temperature · Describe · 4 marks

## Mark scheme (4 marks)

1. Evaporation occurs only at the surface of the liquid, whereas boiling occurs throughout the liquid (in the bulk).
2. Evaporation can occur at any temperature, whereas boiling only occurs at a fixed boiling point.
3. During evaporation, only the higher-energy molecules escape from the surface, so the average kinetic energy of the remaining molecules decreases.
4. Boiling occurs at a constant temperature (the boiling point), with energy supplied used to change state rather than increase temperature.

## Key terms

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

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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-the-differences-between-boiling-and-72a9c90f) · Published by Druglandscape Ltd.