kimia kelas 11 semester 1

ΔHf°H2O=-285,5 KJ/mol
ΔHf°CO2=-393,5 KJ/mol
ΔHf°C3H8=-103 KJ/mol

ΔHc°C3H8
C3H8+7O2->3CO2+8H2O
∑ΔHf° kanan-∑ΔHf°kiri=(3(-393,5)+8(-285,5))-(-103+7(0))
                                    =(-1180,5-2284)+103
                                   =-3361,5 KJ/mol