# Water vapour, carbon dioxide and methane are all described as greenhouse gases. State what is meant by the term 'greenhouse gases' and explain how an increase in the concentration of these gases in the atmosphere is linked to climate change.

> Pearson Edexcel International GCSE Chemistry (4CH1) — 2.3 Gases in the atmosphere · State and Explain · 4 marks

## Mark scheme (4 marks)

1. Greenhouse gases are gases in the atmosphere that trap infra-red radiation (from the Earth's surface) / maintain temperatures on Earth high enough to support life
2. A greater concentration of greenhouse gases means more infra-red radiation is trapped / less infra-red radiation escapes into space
3. This causes the temperature of the Earth's atmosphere to increase / global warming
4. This change in global climate patterns is described as climate change

## Key terms

- [greenhouse gases](https://www.gradenine.co.uk/glossary/greenhouse-gases)
- [climate change](https://www.gradenine.co.uk/glossary/climate-change)

## Related

- [Revision notes for Pearson Edexcel International GCSE Chemistry (4CH1)](https://www.gradenine.co.uk/learn)
- [How to answer "State and 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/water-vapour-carbon-dioxide-and-methane-f5b4c77c) · Published by Druglandscape Ltd.