This question is about alcohols used as alternative fuels.
An investigator measured the heat energy released upon complete combustion of different primary alcohols.
| Alcohol | Formula of one molecule of the alcohol | Energy released in kJ/g\text{kJ/g}kJ/g |
|---|---|---|
| Methanol | CH3OH\text{CH}_3\text{OH}CH3OH | 22.7 |
| Ethanol | C2H5OH\text{C}_2\text{H}_5\text{OH}C2H5OH | 29.7 |
| Propan-1-ol | C3H7OH\text{C}_3\text{H}_7\text{OH}C3H7OH | 33.6 |
| Butan-1-ol | C4H9OH\text{C}_4\text{H}_9\text{OH}C4H9OH | 36.1 |
| Pentan-1-ol | C5H11OH\text{C}_5\text{H}_{11}\text{OH}C5H11OH | 37.8 |
| Octan-1-ol | C8H17OH\text{C}_8\text{H}_{17}\text{OH}C8H17OH | 40.5 |
Calculate the mass of ethanol that must be burned to release the same amount of energy as burning 4.80 g4.80\text{ g}4.80 g of octan-1-ol. Give your answer to 3 significant figures.
12 exam-style questions on AQA GCSE Chemistry 7.2 Reactions of alkenes and alcohols, covering 7.2.1 Structure and formulae of alkenes, 7.2.2 Reactions of alkenes, 7.2.3 Alcohols, and 7.2.4 Carboxylic acids. Each one has a worked solution and a mark scheme showing where the marks go.