Use the following data :

Substance	fracDelta_f H^ominus(500K)kJ mol^-1$\frac{\Delta_f H^{\ominus}(500K)}{kJ mol^{-1}}$	fracS^ominus(500K)J K^-1 mol^-1$\frac{S^{\ominus}(500K)}{J K^{-1} mol^{-1}}$
AB(g)	32	222
A_2(g)$A_2(g)$	6	146
B_2(g)$B_2(g)$	x	280

One mole each of A_2(g)$A_{2}(g)$ and B_2(g)$B_{2}(g)$ are taken in a 1L closed flask and allowed to establish the equilibrium at 500K. A_2(g) + B_2(g) rightleftharpoons 2AB(g)$$A_{2}(g) + B_{2}(g) \rightleftharpoons 2AB(g)$$ The value of x (in textkJ mol^-1$\text{kJ mol}^{-1}$) is .... (Nearest integer) (Given: log K=2.2, R=8.314text J K^-1text mol^-1$\log K=2.2, R=8.314\text{ J K}^{-1}\text{ mol}^{-1}$)