Question

Thermochemical equation for two rocket fuels are given below `:`
`2Al_((s))+(3//2)O_(2(g))rarr Al_(2)O_(3(s)),DeltaH=-1667.8kJ`
`H_(2(g))+1//2O_(2) rarr H_(2)O_((l)),DeltaH=-285.9kJ`

Answer 1

Calorific value of `Al=(-1667.8)/(54)=-30.88kJ //g`
Calorific value of `H_(2)=(-285.9)/(2)=-142.95kJ //g`
Thus `H_(2)` is better rocket fuel.