Question

The dissociation energy of $C{H}_4\left(g\right)$ is $360kcalmo{l}^{-1}$ and that of $C_2{H}_6\left(g\right)$ is $620kcalmo{l}^{-1}$. The $C-C$bond energy

• A. $260kcalmo{l}^{-1}$
• B. $180kcalmo{l}^{-1}$
• C. $130kcalmo{l}^{-1}$
• D. $80kcalmo{l}^{-1}$

Answer 1

The correct option is D $80kcalmo{l}^{-1}$

Let the bond dissociation energy of $C-C$ and $C-H$ bond be $xkcal/mol$ and $ykcal/mol$ respectively.

So, for methane molecule $4y=360$

$y=90$ $kcal/mol$

For ethane molecule, $x+6y=620$

$x+540=620$

$x=80$ $kcal/mol$

Option D