# Iron can be protected from rusting by a process called sacrificial protection, in which a more reactive metal is attached to the iron. Explain why zinc is suitable for use as a sacrificial metal to protect iron, and describe what happens to the zinc over time.

> Pearson Edexcel International GCSE Chemistry (4CH1) — 2.4 Reactivity series · Explain · 4 marks

> Iron structures such as ships' hulls and underground pipelines are vulnerable to corrosion when exposed to water and oxygen.

## Mark scheme (4 marks)

1. Zinc is more reactive than iron (in the reactivity series)
2. Zinc is oxidised / corrodes preferentially instead of the iron
3. Zinc creates a physical barrier, preventing water and oxygen from reaching the iron
4. The zinc is gradually used up / corroded over time and must be replaced

## Key terms

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

## Related

- [Revision notes for Pearson Edexcel International GCSE Chemistry (4CH1)](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/iron-can-be-protected-from-rusting-16ccd7b1) · Published by Druglandscape Ltd.