# Explain what is meant by the term 'isotopes' and describe how two isotopes of the same element differ from each other.

> AQA GCSE Physics (8463) — 4.4.1 Atoms and isotopes · Explain · 4 marks

## Mark scheme (4 marks)

1. Isotopes are atoms of the same element (same number of protons / same atomic number)
2. Isotopes have different numbers of neutrons
3. Isotopes therefore have different mass numbers
4. Correct example given, e.g. Carbon-12 and Carbon-14 both have 6 protons but different numbers of neutrons

## Key terms

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

## Related

- [Revision notes for AQA GCSE Physics (8463)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-what-is-meant-by-the-2f8a85f9) · Published by Druglandscape Ltd.