Methanol, a potential replacement for gasoline as an automotive fuel, can be made from $\mathrm{H}_{2}$ and $\mathrm{CO}$ by the reaction
$$
\mathrm{CO}(g)+2 \mathrm{H}_{2}(g) \rightleftharpoons \mathrm{CH}_{3} \mathrm{OH}(g)
$$
At $500.0 \mathrm{~K},$ this reaction has $K_{\mathrm{p}}=6.25 \times 10^{-3}$ . Calculate $\Delta G_{500}^{\circ}$ for this reaction in units of kilojoules.