# Crystallisation can be used to obtain a pure salt from a solution. Describe the steps involved in obtaining pure copper sulfate crystals from a copper sulfate solution.

> WJEC GCSE Chemistry (Wales) — 1.3 Water · Describe · 4 marks

## Mark scheme (4 marks)

1. Heat / warm the copper sulfate solution (in an open container) to allow the solvent (water) to evaporate
2. Continue heating until a saturated solution is formed / until crystals start to appear / until the volume of solution has reduced
3. Allow the solution to cool so that crystals form / grow
4. Filter the crystals from the remaining solution and allow them to dry

## Key terms

- [crystallisation](https://www.gradenine.co.uk/glossary/crystallisation)

## Related

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Source: [GradeNine](https://www.gradenine.co.uk/q/crystallisation-can-be-used-to-obtain-18e1258c) · Published by Druglandscape Ltd.