# Isotopes of an element have the same chemical properties but different physical properties. Explain why isotopes of the same element have the same chemical properties but may have different physical properties.

> Eduqas GCSE Chemistry — C1 Atomic structure and the periodic table · Explain · 4 marks

## Mark scheme (4 marks)

1. Isotopes have the same number of protons / same atomic number
2. Isotopes have the same number of electrons (and the same electron arrangement / configuration)
3. Chemical properties depend on the number / arrangement of electrons, so isotopes react in the same way
4. Isotopes have different numbers of neutrons, giving them different mass numbers / different masses, which affects physical properties such as density or melting point

## Key terms

- [isotopes](https://www.gradenine.co.uk/glossary/isotopes)
- [chemical properties](https://www.gradenine.co.uk/glossary/chemical-properties)
- [physical properties](https://www.gradenine.co.uk/glossary/physical-properties)

## 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/isotopes-of-an-element-have-the-ae9118e2) · Published by Druglandscape Ltd.