Chemistry - Thermochemistry Question with Solution | TestHub

On the basis of the following thermochemical data: $\left(\Delta {\mathrm{fG}}^{\circ }{\mathrm{H}}_{\text{(aq) }}^{+}=0\right)$ $$\begin{array}{rl}& {\mathrm{H}}_2\mathrm{O}(\ell )\to {\mathrm{H}}^{+}(\mathrm{aq})+{\mathrm{OH}}^{-}(\mathrm{aq});\Delta \mathrm{H}=57.32\mathrm{kJ}\\ & {\mathrm{H}}_2(\mathrm{g})+\frac{1}{2}{\mathrm{O}}_2(\mathrm{g})\to {\mathrm{H}}_2\mathrm{O}(\ell );\Delta \mathrm{H}=-286.20\mathrm{kJ}\end{array}$$ The value of enthalpy of formation of ${\mathrm{OH}}^{-}$ion at $25^{\circ }\mathrm{C}$ is: