The enthalpy change $\left(\mathrm{\Delta }H\right)$ for the process ${\mathrm{N}}_2{\mathrm{H}}_4\left(g\right)\to 2\mathrm{N}\left(g\right)+4\mathrm{H}\left(g\right)\text{ is }1724\mathrm{kJ}{\mathrm{mol}}^{-1}$ if the bond energy of $\mathrm{N}-\mathrm{H}$ bond in ammonia is $391\mathrm{kJ}{\mathrm{mol}}^{-1}$ what is the bond energy of  $\mathrm{N}-\mathrm{H}$ bond is ${\mathrm{N}}_2{\mathrm{H}}_4$