# Ethanol can be converted into ethanoic acid by microbial oxidation. Ethanoic acid belongs to the homologous series of carboxylic acids. Explain why ethanoic acid is classified as a member of the carboxylic acid homologous series, and describe how the properties of ethanoic acid are similar to those of propanoic acid.

> Pearson Edexcel International GCSE Chemistry (4CH1) — 4.6 Carboxylic acids · Explain · 4 marks

> Ethanol undergoes microbial oxidation to produce ethanoic acid. Ethanoic acid and propanoic acid are both members of the carboxylic acid homologous series.

## Mark scheme (4 marks)

1. Ethanoic acid contains the functional group –COOH
2. All members of a homologous series share the same functional group and have similar chemical properties
3. Both ethanoic acid and propanoic acid show typical acidic properties, such as reacting with metals / carbonates / alkalis
4. Ethanoic acid and propanoic acid differ only by a –CH₂– unit / differ in chain length but have the same general formula

## Key terms

- [homologous series](https://www.gradenine.co.uk/glossary/homologous-series)
- [carboxylic acids](https://www.gradenine.co.uk/glossary/carboxylic-acids)
- [microbial oxidation](https://www.gradenine.co.uk/glossary/microbial-oxidation)

## Related

- [Revision notes for Pearson Edexcel International GCSE Chemistry (4CH1)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/ethanol-can-be-converted-into-ethanoic-8dc4f0f6) · Published by Druglandscape Ltd.