# Ethanol can be produced by two different industrial methods: fermentation of glucose, and the hydration of ethene. Describe fermentation as a method of producing ethanol, and state one advantage and one disadvantage of using fermentation compared with the hydration of ethene.

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

## Mark scheme (5 marks)

1. Glucose is broken down / converted to ethanol (and carbon dioxide) by yeast / enzymes
2. The reaction requires warm/suitable temperatures (approximately 25–37 °C) / anaerobic (absence of oxygen) conditions
3. The ethanol produced must be separated / purified by distillation
4. One advantage: fermentation uses a renewable raw material (glucose/sugar/plants/biomass) / is a sustainable/carbon-neutral process
5. One disadvantage: fermentation is a slow/batch process / produces a dilute solution of ethanol / requires distillation to concentrate the product

## Key terms

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

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Source: [GradeNine](https://www.gradenine.co.uk/q/ethanol-can-be-produced-by-two-62eb1530) · Published by Druglandscape Ltd.