The table below shows some mean bond enthalpy data:
| Bond | Mean bond enthalpy / kJ mol−1\text{kJ mol}^{-1}kJ mol−1 |
|---|---|
| C≡O\text{C}\equiv\text{O}C≡O | 1077 |
| H−H\text{H}-\text{H}H−H | 436 |
| C−H\text{C}-\text{H}C−H | 413 |
| C−O\text{C}-\text{O}C−O | 358 |
| O−H\text{O}-\text{H}O−H | 463 |
What is the enthalpy change, in kJ mol−1\text{kJ mol}^{-1}kJ mol−1, for the gas-phase synthesis of methanol shown below?
CO(g)+2H2(g)→CH3OH(g) \text{CO(g)} + 2\text{H}_2\text{(g)} \rightarrow \text{CH}_3\text{OH(g)} CO(g)+2H2(g)→CH3OH(g)−547 kJ mol−1-547\text{ kJ mol}^{-1}−547 kJ mol−1
−111 kJ mol−1-111\text{ kJ mol}^{-1}−111 kJ mol−1
+111 kJ mol−1+111\text{ kJ mol}^{-1}+111 kJ mol−1
+352 kJ mol−1+352\text{ kJ mol}^{-1}+352 kJ mol−1