Alcohols
Alcohols
- Alcohols contain the –OH functional group; the key one is ethanol.
- Ethanol burns well (a fuel) and dissolves many substances (a solvent).
Practice
The functional group of alcohols is:
Alcohols contain the –OH group; ethanol is the main example.
Practice
Ethanol is used as a: (Choose all that apply.)
Ethanol burns well (fuel) and dissolves many substances (solvent).
Two ways to make ethanol
| Method | Conditions | Notes |
|---|---|---|
| fermentation of glucose | yeast, 25–35 °C, no oxygen | renewable sugar, but slow and impure |
| addition of steam to ethene | 300 °C, 60 atm, acid catalyst | fast and pure, but uses petroleum |
- In fermentation, yeast turns glucose → ethanol + carbon dioxide.
Practice
Making ethanol by fermentation uses:
Yeast ferments glucose without oxygen at 25–35 °C, making ethanol and carbon dioxide.
You've got it
Key idea
- alcohols have the –OH group; ethanol is a fuel and a solvent
- fermentation (yeast, renewable, slow/impure) vs steam + ethene (fast/pure, non-renewable)
- fermentation: glucose → ethanol + carbon dioxide