# A student has two solutions: one containing sulfuric acid and one containing ethanoic acid, both at the same concentration. Explain why the sulfuric acid solution has a lower pH than the ethanoic acid solution.

> Edexcel GCSE Chemistry (1CH0) — 3.1 Acids · Explain · 4 marks

## Mark scheme (4 marks)

1. Sulfuric acid is a strong acid
2. Ethanoic acid is a weak acid
3. Sulfuric acid is completely ionised in aqueous solution / releases (nearly) all of its H+ ions
4. Ethanoic acid is only partially ionised / releases only a small number of H+ ions, so sulfuric acid produces a higher concentration of H+ ions giving a lower pH

## Key terms

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

## 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)
- [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-has-two-solutions-one-8a977633) · Published by Druglandscape Ltd.