Question

C(graphite)+O2(g)-->CO2(g) delta H rxn =-393.5 kJ/mol
H2(g) +1/2 O2 (g) --> H2O(l) delta H= -285.8 kJ/mol
2C2H6(g) +7O2(g) --> 4CO2(g)+6H2O(l) delta H =-3119.6 kJ/mol
Calculate the enthalpy change for the reaction below:
2 C(graphite) +3H2(g) --> C2H6(g)