# Ethanoic acid is a carboxylic acid found in vinegar. Explain why ethanoic acid is described as a weak acid, and describe two chemical reactions that show it behaves as an acid.

> Eduqas A-Level Chemistry — 2.7 Alcohols and carboxylic acids · Explain and Describe · 5 marks

## Mark scheme (5 marks)

1. A weak acid is only partially dissociated (ionised) in water / does not fully ionise
2. First chemical reaction described — reaction with a metal (e.g. magnesium/zinc/iron) producing hydrogen gas
3. First reaction: also produces a salt (named or described as a metal ethanoate)
4. Second chemical reaction described — reaction with a carbonate (or metal oxide/alkali/base) producing named products
5. Both reactions linked to acid behaviour — identifies that H⁺ ions / protons are donated or that the acid is neutralised in both cases

## Key terms

- [weak acid](https://www.gradenine.co.uk/glossary/weak-acid)
- [carboxylic acid](https://www.gradenine.co.uk/glossary/carboxylic-acid)

## Related

- [Revision notes for Eduqas A-Level Chemistry](https://www.gradenine.co.uk/learn)
- [How to answer "Explain and Describe" 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/ethanoic-acid-is-a-carboxylic-acid-5b1fbc74) · Published by Druglandscape Ltd.