# Substance X has a melting point of 1083 °C and substance Y has a melting point of −39 °C. Using ideas about forces between particles, explain why these two substances have such different melting points.

> Eduqas GCSE Chemistry — 2.1 Bonding, structure and properties · Explain · 4 marks

> Substance X is a solid metal at room temperature. Substance Y is a liquid at room temperature.

## Mark scheme (4 marks)

1. The amount of energy needed to change state depends on the strength of the forces between particles
2. Substance X has stronger forces between its particles than substance Y
3. More energy is needed to overcome the forces between particles in X, giving it a higher melting point
4. Substance Y has weaker forces between its particles, so less energy is needed to separate them, giving it a much lower melting point

## Key terms

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

## Related

- [Revision notes for Eduqas GCSE Chemistry](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/substance-x-has-a-melting-point-c04430ef) · Published by Druglandscape Ltd.