# Nitrogen makes up approximately 78% of the Earth's atmosphere, yet it is not classified as a greenhouse gas. Explain why nitrogen does not contribute to the greenhouse effect, and state two gases that are classified as greenhouse gases.

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

> The Earth's atmosphere is composed of several gases. Some of these gases are described as greenhouse gases, whilst others, including nitrogen, are not.

## Mark scheme (4 marks)

1. Greenhouse gases trap infra-red radiation (from the Earth's surface) / nitrogen does not absorb or trap infra-red radiation
2. Therefore nitrogen does not raise/maintain the temperature of the atmosphere / does not contribute to warming the Earth
3. First correct greenhouse gas named: water vapour OR carbon dioxide
4. Second correct greenhouse gas named: methane (or a different correct gas from the list above not already given)

## Key terms

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

## Related

- [Revision notes for Pearson Edexcel International GCSE Chemistry (4CH1)](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/nitrogen-makes-up-approximately-78-of-fb9231f4) · Published by Druglandscape Ltd.