# A student is assessing the purity of a sample of copper(ii) sulfate solution by adding a small amount to a sample of water. They record the temperature of the water before and after the addition. Explain how the student can use the data to determine the purity of the copper(ii) sulfate solution.

> OCR A-Level Chemistry A (H432) — 1.1 Practical skills assessed · Explain · 4 marks

## Mark scheme (4 marks)

1. Understanding of the principle of the experiment
2. Mention of a relevant factor that affects purity
3. Mention of a relevant factor that affects temperature change
4. Mention of a relevant factor that affects the temperature change and purity

## Related

- [Revision notes for OCR A-Level Chemistry A (H432)](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-is-assessing-the-purity-41473cf9) · Published by Druglandscape Ltd.