For a certain reaction, $\Delta H^0$ is $-345$ kJ and $\Delta S^0$ is $-123\ \text{JK}^{-1}$. At what temperature the change over from spontaneous to nonspontaneous will occur?

For a reaction to be spontaneous at all temperatures, the values of enthalpy change and entropy change should be

Find $\Delta n$ when 1 mol of each $\text{NH}_{3(g)}$ and $\text{HCl}_{(g)}$, reacts to form solid $\text{NH}_4\text{Cl}$.

What is the solubility product of binary sparingly soluble salt BA if 100 mL saturated solution of salt consist $10^{-4}$ moles at room temperature?