Calculate standard molar entropy of ${\mathrm{O}}_2\left(\mathrm{g}\right)$ from the following thermodynamic data at $300 \mathrm{K}$

$\begin{array}{l}4\mathrm{Cr}\left(s\right)+3{\mathrm{O}}_2\left(g\right)⟶2{\mathrm{Cr}}_2{\mathrm{O}}_3\left(s\right)\\ \mathrm{\Delta }{G}^{\circ }=-2093.4\mathrm{kJ}/\mathrm{mol}\\ \mathrm{\Delta }{H}_f^{\circ }{\mathrm{Cr}}_2{\mathrm{O}}_3\left(s\right)=-1129.05\mathrm{kJ}/\mathrm{mole}\\ \begin{array}{l}{S}_m^{\circ }\mathrm{Cr}\left(s\right)=24\mathrm{J}/\mathrm{Kmole}\\ S_m^{\circ }{\mathrm{Cr}}_2{\mathrm{O}}_3\left(s\right)=81\mathrm{J}/\mathrm{Kmol}\end{array}\end{array}$