# A student investigates the decomposition of hydrogen peroxide solution at two different temperatures. At the higher temperature, the reaction produces oxygen gas much more quickly. Using the Maxwell-Boltzmann distribution, explain why increasing the temperature causes the rate of the decomposition reaction to increase.

> Edexcel A-Level Chemistry (9CH0) — 9.1 Rates and the Maxwell-Boltzmann distribution · Explain · 5 marks

> Hydrogen peroxide decomposes according to the equation: 2H₂O₂(aq) → 2H₂O(l) + O₂(g). The student notices that at a higher temperature the reaction is noticeably faster.

## Mark scheme (5 marks)

1. The Maxwell-Boltzmann distribution shows the spread/range of energies of particles in a reaction mixture
2. There is a minimum energy required for a reaction to occur, called the activation energy
3. At a higher temperature, particles have more (kinetic) energy on average / the distribution shifts to the right
4. A greater proportion / more particles have energy equal to or greater than the activation energy at the higher temperature
5. There are more successful/effective collisions per unit time, so the rate of reaction increases

## Key terms

- [Maxwell-Boltzmann distribution](https://www.gradenine.co.uk/glossary/maxwell-boltzmann-distribution)

## Related

- [Revision notes for Edexcel A-Level Chemistry (9CH0)](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/a-student-investigates-the-decomposition-of-0084619e) · Published by Druglandscape Ltd.