# Ethanoic acid is a carboxylic acid. Explain what happens when ethanoic acid is added to sodium carbonate solution, and describe how the products of this reaction could be used to identify that a carboxylic acid was present.

> WJEC A-Level Chemistry (Wales) — 2.7 Alcohols and carboxylic acids · Explain · 5 marks

> Vinegar contains ethanoic acid, which reacts with sodium carbonate solution. This reaction can be used as a test for carboxylic acids.

## Mark scheme (5 marks)

1. Ethanoic acid reacts with sodium carbonate (solution)
2. Carbon dioxide gas is produced / given off
3. A salt (sodium ethanoate) and water are also formed
4. The carbon dioxide gas is passed through / bubbled into limewater
5. The limewater turns milky / cloudy, confirming carbon dioxide is present and therefore a carboxylic acid was present

## Key terms

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

## Related

- [Revision notes for WJEC A-Level Chemistry (Wales)](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/ethanoic-acid-is-a-carboxylic-acid-06d50612) · Published by Druglandscape Ltd.