# A student adds a small piece of solid manganese(IV) oxide to a solution of hydrogen peroxide. The student notices that oxygen gas is produced much more quickly than when no manganese(IV) oxide is present. The manganese(IV) oxide remains unchanged at the end of the reaction. Explain how the manganese(IV) oxide increases the rate of this reaction.

> Edexcel GCSE Chemistry (1CH0) — 7.1 Rates of reaction · Explain · 4 marks

## Mark scheme (4 marks)

1. Manganese(IV) oxide acts as a catalyst
2. The catalyst provides a different (reaction) pathway / alternative route for the reaction
3. This different pathway has a lower activation energy
4. More (colliding) particles now have at least the activation energy, so there is a higher rate of successful collisions / the rate of reaction increases

## Related

- [Revision notes for Edexcel GCSE Chemistry (1CH0)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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