For the reaction $\mathrm{A}_{(\mathrm{g})} \rightarrow(\mathrm{B})_{(\mathrm{g})}$, the value of the equilibrium constant at 300 K and 1 atm is equal to 100.0 . The value of $\Delta \mathrm{G}$ for the reaction at 300 K and 1 atm in J mol ${ }^{-1}$ is -xR , where x is $\_\_\_\_$ (Rounded off to the nearest integer) $\left(\mathrm{R}=8.31 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}\right.$ and $\left.\mathrm{In} 10=2.3\right)$