Molar enthalpy of combustion of $C_2{H}_2\left(g\right),C_{,}graphite$ and ${\mathrm{H}}_2\left(\mathrm{g}\right)$ are $-1300,-394\text{ and }-286 \mathrm{kJ}/\mathrm{mole}$ respectively, then, calculate Bond enthalpy of $C\equiv C$bond in $kJ/$mole :

Given : $\mathrm{\Delta }{H}_{\text{sub }}\left({\mathrm{C}}_{\text{graphite }}\right)=715\mathrm{kJ}/\text{ mole }$

$\Delta H_{B}E(H-H)=436 kJ/mole$

$\Delta H_{B}E(C-H)=413 kJ/mole$