Use the following data : TABLE One mole each of $\mathrm{A}_{2}(\mathrm{~g})$ and $\mathrm{B}_{2}(\mathrm{~g})$ are taken in a 1L closed flask and allowed to establish the equilibrium at 500 K . $\\ \mathrm{A}_{2}(\mathrm{~g})+\mathrm{B}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{AB}(\mathrm{g})\\$ The value of $\mathrm{x}\left(\mathrm{in} \mathrm{kJ} \mathrm{mol}^{-1}\right)$ is $\_\_\_\_$ (Nearest integer) $\\$(Given: $\log \mathrm{K}=2.2 \mathrm{R}=8.3 \mathrm{JK}^{-1} \mathrm{~mol}^{-1}$ )