From the following bond energies:
H - H bond energy: 431.37 kJ mol-1
C = C bond energy: 606.10 kJ mol-1
C - C bond energy: 336.49 kJ mol-1
C - H bond energy: 410.50 kJ mol-1
Enthalpy for the reaction,
will be:
-243.6 kJ mol-1
-120.0 kJ mol- 1
553.0 kJ mol-1
1523.6 kJ mol- 1