Carbon monoxide reacts with hydrogen to form methanol vapour.
CO+2H2→CH3OH \mathrm{CO + 2H_{2} \rightarrow CH_{3}OH} CO+2H2→CH3OHA carbon monoxide molecule contains one C≡O bond. A methanol molecule contains three C–H bonds, one C–O bond and one O–H bond.
The table shows average bond energies.
| Bond | Bond energy (kJ/mol) |
|---|---|
| C≡O | 1077 |
| H–H | 436 |
| C–H | 413 |
| C–O | 358 |
| O–H | 463 |
Calculate the energy change, in kJ/mol\text{kJ/mol}kJ/mol, for the equation as written.
Show your working.
106 exam-style questions on OCR GCSE Chemistry 3.2 Energetics, covering 3.2.1 Exothermic and endothermic reactions and reaction profiles and 3.2.2 Calculating energy change from bond energies. Each one has a worked solution and a mark scheme showing where the marks go.