A student investigated the energy released by burning various alcohols. They used a spirit burner to heat 150 cm3 of water by 25∘C25^\circ\text{C}25∘C for each fuel.
Table 1 shows some of their results.
Table 1
| Alcohol | Initial mass of spirit burner and alcohol (g) | Final mass of spirit burner and alcohol (g) | Mass of alcohol used (g) |
|---|---|---|---|
| Methanol | 115.80 | 115.12 | 0.68 |
| Ethanol | 134.45 | 133.91 | |
| Propanol | 142.10 | 141.64 | 0.46 |
| Butanol | 158.35 | 157.97 | 0.38 |
Calculate the mass of ethanol used.
94 exam-style questions on Edexcel GCSE Chemistry 8.2 Heat energy changes in chemical reactions, covering 8.2.1 Exothermic and endothermic changes, 8.2.2 Bond breaking, bond making and overall energy change, 8.2.3 Calculating energy change from bond energies, and 8.2.4 Activation energy and reaction profiles. Each one has a worked solution and a mark scheme showing where the marks go.