= (4. CO2 + 6. H2O) – (2. C2H6 + 7. O2) = (4.mol– 394 kJ/mol + 6mol. – 242,0 kJ/mol) –(2. –84,7 kJ + 7. mol.0 kJ/mol) = (– 1.576 kJ + ( – 1.452 kJ ) –(– 169,4 kJ )