Use the following data :

One mole each of $$A_{2}(g)$$ and $$B_{2}(g)$$ are taken in a 1 L closed flask and allowed to establish the equilibrium at 500K
$$A_{2}(g)+B_{2}(g)\rightleftharpoons2AB(g)$$
The value of x $$(in kJ mol^{-1})$$ is ____ . (Nearest integer)
(Given: log K=2.2 R= 8.3 kJ $$K^{-1} mol^{-1}$$)