Consider the reactions `:`
`C_((s))+2H_(2(g)) rarr CH_(4(g)), DeltaH=-X kcal`
`C_((g))+4H_((g)) rarr CH_(4(g)),DeltaH-X_(1)kcal`
`CH_(4(g))rarr CH_(3(g))+H_((g)), DeltaH=+Ykcal`
The average bond energy of `C-H` bond is `:`

Options

A. `(X)/(4)` K cal. `mol^(-1)`
B. Y K cal. `mol^(-1s)`
C. `(X_(1))/(4)` K cal. `mol^(-1)`
D. `X_(1)` K cal. `mol^(-1)`

Answer

C

Explanation

`CH_(4(g))rarr C_((g))+4H_((g)) , Delta H= + x_(1) KCal`
`therefore` B.E. of C-H bond `=(x_(1))/(4) KCal mol^(-1)`