# Tag Info

The enthalpy of combustion of hydrogen is 286kJ/mol i.e. 286kJ per 18g of water produced. So if the original mass of water in your comet is M (in kg), and you manage to split it completely into hydrogen and oxygen, then the energy released when you react the hydrogen and oxygen is given by:  E = 2.86 \times 10^5 \frac{M}{0.018} \approx 1.6 \times 10^7 M ...