Chapter 21, Problem 11E

The standard Gibbs energies of formation, ${\Delta }_{r}G°$ , for ${\text{Na}}_{\text{2}}\text{O}$ (s) and ${\text{Na}}_{\text{2}}{\text{O}}_{\text{2}}$ (s) are −379.09 kJ ${\text{mol}}^{-1}$ and −449.63 kJ ${\text{mol}}^{-1}$ respectively, at 298 K. Calculate the equilibrium constant for the reaction below at 298 K. Is ${\text{Na}}_{\text{2}}{\text{O}}_{\text{2}}$ (s) thermodynamically stable with respect to ${\text{Na}}_{\text{2}}\text{O}$ (s) and ${\text{O}}_{\text{2}}$ (g) at 298 K?
$N{a}_2{O}_2\to N{a}_{2}o(s)+\frac{1}{2}{o}_2(g)$