Calculate ΔG° at 25°C for the reaction. R=8.314 J/K-mol. BaSO4(s) ⇌ Ba⁺²(aq) + SO4⁻²(aq). What is the value of the solubility product constant, Ksp, for this reaction? Gibbs free energy of formations in kJ: BaSO4: -1353, Ba⁺²: -561, SO42-: -742