# A scientist carries out electrolysis of molten lead bromide using inert electrodes. Explain what happens at each electrode during this process.

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

> Lead bromide is an ionic compound that can be electrolysed when melted. The molten liquid acts as the electrolyte, allowing ions to move freely through it.

## Mark scheme (4 marks)

1. Lead ions (Pb²⁺) are positively charged ions (cations) that move towards the cathode (negative electrode)
2. At the cathode, lead ions gain electrons (reduction) to form lead metal
3. Bromide ions (Br⁻) are negatively charged ions (anions) that move towards the anode (positive electrode)
4. At the anode, bromide ions lose electrons (oxidation) to form bromine gas

## Key terms

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

## 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/a-scientist-carries-out-electrolysis-of-12d38ed2) · Published by Druglandscape Ltd.