Consider the following reversible reaction, $\mathrm{A}\left(\mathrm{g}\right)+\mathrm{B}\left(\mathrm{g}\right)\to \mathrm{AB}\left(\mathrm{g}\right)$
The activation energy of the backward reaction exceeds that of the forward reaction by 2RT (in Jmol ^-1).If the pre-exponential factor of the forward reaction is 4 times that of the reverse reaction, the absolute value of ${\mathrm{\Delta G}}^0\left(\text{ in }{\mathrm{jmol}}^{-1}\right)$ for the reaction at 300 K is___
(Given $\mathrm{In}\left(2\right)=0.7,\mathrm{RT}=2500\mathrm{J}{\mathrm{mol}}^{-1}$at 300 K and G is the Gibbs energy)