# Explain how increasing the concentration of hydrochloric acid increases the rate of its reaction with marble chips.

> AQA GCSE Chemistry (8462) — 4.6.1 Rate of reaction · Explain · 4 marks

## Mark scheme (4 marks)

1. Increasing concentration means particles are closer together (in solution)
2. Collisions between reacting particles are more frequent
3. There is a higher rate of successful collisions
4. Therefore the rate of reaction increases

## Key terms

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

## Related

- [Revision notes for AQA GCSE Chemistry (8462)](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)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-increasing-the-concentration-of-70067260) · Published by Druglandscape Ltd.