The `H-H` bond energy is `430KJmol^(-1)` and `Cl-Cl` bond energy is `240KJmol^(-1)` . `DeltaH` for `HCl` is `-90KJ` . The `H-Cl` bond energy is about

Options

A. `425KJmol^(-1)`
B. `213KJmol^(-1)`
C. `306KJmol^(-1)`
D. `180KJmol^(-1)`

Answer

B

Explanation

`(1)/(2)H_(2)+(1)/(2)Cl_(2)rarrHCl,DeltaH=-90KJ`
`:. DeltaH=(1)/(2)e_(H-H)+(1)/(2)e_(Cl-Cl)`
or `-90=(1)/(2)xx430+(1)/(2)xx240-e_(H-Cl)`
`:. e_(H-Cl)=425KJmol^(-1)`