In a core practical, a student burns four alcohols in turn to heat 100 g of water. The student expects the temperature rise per mole of alcohol burned to increase steadily with the number of carbon atoms in the molecule.
| Alcohol | MrM_rMr | Mass burned (g) | Temperature rise (∘C^\circ\mathrm{C}∘C) |
|---|---|---|---|
| ethanol | 46 | 1.15 | 25.0 |
| propan-1-ol | 60 | 0.90 | 22.2 |
| butan-1-ol | 74 | 1.11 | 21.6 |
| pentan-1-ol | 88 | 0.88 | 24.4 |
Which alcohol gave a result that does not fit the expected pattern?
ethanol
propan-1-ol
butan-1-ol
pentan-1-ol
43 exam-style questions on Edexcel GCSE Chemistry 10.4 Alcohols and carboxylic acids, covering 10.4.1 Alcohols and the -OH functional group, 10.4.2 Carboxylic acids and the -COOH functional group, 10.4.3 Oxidation of alcohols and homologous series, and 10.4.4 Fermentation and fractional distillation of ethanol. Each one has a worked solution and a mark scheme showing where the marks go.