The enthalpy change for the reaction, C2H4(g) + 3O2(g) ⟶2CO2(g) + 2H2O(g) is called:
Enthalpy of formation
Enthalpy of combustion
Enthalpy of vaporization
Enthalpy of sublimation
For the reaction C2H4(g)+3O2(g)→2CO2(g)+2H2O(l), the difference between enthalpy change and internal energy change is: