# When a solid is heated to its melting point, it turns into a liquid. Explain, in terms of particles, what happens to the arrangement and movement of particles during melting, and why the substance can now flow.

> Pearson Edexcel International GCSE Chemistry (4CH1) — 1.1 States of matter · Explain · 4 marks

## Mark scheme (4 marks)

1. During melting, the particles gain (kinetic) energy (from heating)
2. The regular/fixed arrangement of particles breaks down / particles are no longer held in fixed positions
3. Particles in a liquid are still close together but can move/slide/flow past one another
4. Because particles can move/slide past one another, the liquid can flow / takes the shape of its container

## Key terms

- [melting point](https://www.gradenine.co.uk/glossary/melting-point)
- [liquid](https://www.gradenine.co.uk/glossary/liquid)
- [particles](https://www.gradenine.co.uk/glossary/particles)

## Related

- [Revision notes for Pearson Edexcel International GCSE Chemistry (4CH1)](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/when-a-solid-is-heated-to-f7ea7d4e) · Published by Druglandscape Ltd.