# Methanol and ethanol are both members of the alcohol homologous series. State two structural features that all alcohols share, and explain why methanol is considered more toxic to humans than ethanol.

> Cambridge International IGCSE Chemistry (0620) — 11.6 Alcohols · State and Explain · 4 marks

## Mark scheme (4 marks)

1. All alcohols contain an –OH (hydroxyl) functional group
2. All alcohols contain a carbon chain / carbon skeleton / hydrocarbon chain bonded to the –OH group
3. Methanol is oxidised / broken down in the body to methanal (formaldehyde) / methanoic acid, which is toxic / damages the optic nerve / can cause blindness
4. Ethanol is metabolised to ethanal / ethanoic acid, which is less harmful / less toxic than the products from methanol metabolism; so methanol causes greater harm at equivalent doses

## Key terms

- [homologous series](https://www.gradenine.co.uk/glossary/homologous-series)
- [toxic](https://www.gradenine.co.uk/glossary/toxic)

## Related

- [Revision notes for Cambridge International IGCSE Chemistry (0620)](https://www.gradenine.co.uk/learn)
- [How to answer "State and Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/methanol-and-ethanol-are-both-members-36b585bd) · Published by Druglandscape Ltd.