For the reaction, $CO\left(g\right)+\frac{1}{2}{O}_2\left(g\right)\to C{O}_2\left(g\right)$  at 300 K. Calculate the standard Gibbs free energy change is $-\text{X}$ , when the standard Gibbs energies of formation for $C{O}_2\text{ and }CO\text{ are }-394\text{ and}-137kJmo{l}^{-1},$ respectively, the value of  $\text{X}$ is____