# Describe how you would test for each of the following gases, and state the positive result in each case: hydrogen, oxygen, and carbon dioxide.

> AQA GCSE Chemistry (8462) — 4.8.2 Identification of common gases · Describe · 4 marks

## Mark scheme (4 marks)

1. Test for hydrogen: hold a lit splint to the gas / at the mouth of the test tube
2. Positive result for hydrogen: squeaky pop (sound)
3. Test for oxygen: insert a glowing splint into the gas
4. Positive result for oxygen: the glowing splint relights / reignites

## Key terms

- [hydrogen](https://www.gradenine.co.uk/glossary/hydrogen)
- [oxygen](https://www.gradenine.co.uk/glossary/oxygen)
- [carbon dioxide](https://www.gradenine.co.uk/glossary/carbon-dioxide)

## Related

- [Revision notes for AQA GCSE Chemistry (8462)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" 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/describe-how-you-would-test-for-a6c8eabf) · Published by Druglandscape Ltd.