# Carbon-12 and carbon-14 are both isotopes of carbon. Explain why carbon-12 and carbon-14 have the same chemical properties but different physical properties.

> Cambridge International IGCSE Chemistry (0620) — 2.3 Isotopes · Explain · 4 marks

## Mark scheme (4 marks)

1. Both isotopes have the same number of protons / same atomic number (6)
2. Chemical properties are determined by the number of electrons / same electron arrangement
3. The isotopes have different numbers of neutrons (carbon-12 has 6 neutrons; carbon-14 has 8 neutrons)
4. Different numbers of neutrons give different masses / relative atomic masses, causing different physical properties (e.g. different densities / melting points)

## 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 Cambridge International IGCSE Chemistry (0620)](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/carbon-12-and-carbon-14-are-both-isotopes-a3838d54) · Published by Druglandscape Ltd.