# During the electrolysis of copper sulfate solution, copper is deposited at one electrode and oxygen gas is produced at the other. Explain what happens at each electrode during this process, including the movement and behaviour of ions.

> OCR GCSE Chemistry A: Gateway Science (J248) — C3.4 Electrolysis · Explain · 4 marks

> A student sets up an electrolysis cell using copper sulfate solution as the electrolyte and two inert carbon electrodes connected to a power supply.

## Mark scheme (4 marks)

1. Copper ions (Cu²⁺) are positively charged ions (cations) that move towards the cathode (negative electrode)
2. At the cathode, copper ions gain electrons (reduction), forming copper metal which is deposited
3. Sulfate / hydroxide ions (anions) are negatively charged and move towards the anode (positive electrode)
4. At the anode, water molecules / hydroxide ions lose electrons (oxidation) and oxygen gas is produced

## Key terms

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

## Related

- [Revision notes for OCR GCSE Chemistry A: Gateway Science (J248)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/during-the-electrolysis-of-copper-sulfate-7e9e9ae3) · Published by Druglandscape Ltd.