# A student carries out a reaction between hydrogen and chlorine to produce hydrogen chloride. Write the word equation for this reaction, then explain why it is important that the student checks the hazard information for all substances involved before starting the experiment.

> Edexcel GCSE Chemistry (1CH0) — 0 Formulae, equations and hazards · Explain · 4 marks

## Mark scheme (4 marks)

1. Correct word equation: hydrogen + chlorine → hydrogen chloride
2. Hazard information identifies risks/dangers associated with the substances
3. So that the student can take appropriate precautions / use correct safety measures
4. Reference to a specific hazard of any named substance (e.g. chlorine is toxic/poisonous, hydrogen is flammable, hydrogen chloride is corrosive/toxic)

## Key terms

- [word equation](https://www.gradenine.co.uk/glossary/word-equation)
- [hazard information](https://www.gradenine.co.uk/glossary/hazard-information)

## Related

- [Revision notes for Edexcel GCSE Chemistry (1CH0)](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/a-student-carries-out-a-reaction-c152f6fc) · Published by Druglandscape Ltd.