From the following bond energies: `H--H` bond energy: `431.37KJmol^(-1)`
`C=C` bond energy: `606.10KJmol^(-1)`
`C--C` bond energy: `336.49KJmol^(-1)`
`C--H` bond energy: `410.50KJmol^(-1)`
Enthalpy for the reaction will be:
`overset(H)overset(|)underset(H)underset(|)(C)=overset(H)overset(|)underset(H)underset(|)(C)+H-H to Hoverset(H)overset(|)underset(H)underset(|)(C)-overset(H)overset(|)underset(H)underset(|)(C)-H`

Options

A. `553.0KJmol^(-1)`
B. `1523.6KJmol^(-1)`
C. `-243.6KJmol^(-1)`
D. `-120.0KJmol^(-1)`

Answer

B

Explanation

For reaction
`DeltaH_(r)=-[4xxBE_(C-H)+1BE_(H=-H)]`
`-[6xxBE_(C-H)+1xxBE_(C-C)]`
`=(4xx410.50+1xx606.10+1xx431.37)`
`-[(6xx410.50)+(1xx336.49)]`
`=-120.0KJmol^(-1)`