In which of the following conditions will a reaction always be spontaneous at all temperatures?

At constant pressure and temperature,the direction of any spontaneous chemical reaction is towards the state where there is a decrease in

For the reaction $A \to B$,$\Delta H = 4 \, kcal \, mol^{-1}$ and $\Delta S = 10 \, cal \, K^{-1} \, mol^{-1}$. At what temperature $(K)$ will the reaction become spontaneous?

In the conversion of limestone to lime,$CaCO_{3(s)} \rightarrow CaO_{(s)} + CO_{2(g)}$,the values of $\Delta H^{\circ}$ and $\Delta S^{\circ}$ are $+179.1 \ kJ \ mol^{-1}$ and $160.2 \ J \ K^{-1} \ mol^{-1}$ respectively at $298 \ K$ and $1 \ bar$. Assuming that $\Delta H^{\circ}$ and $\Delta S^{\circ}$ do not change with temperature,the temperature above which the conversion of limestone to lime will be spontaneous is ........... $K$.

For a certain reaction, $\Delta H^{\circ} = 40 \text{ kJ}$ and $\Delta S^{\circ} = 80 \text{ JK}^{-1}$. Find the temperature at which $\Delta G^{\circ} = 0$. (in $\text{ K}$)

For a certain reaction,$\Delta H = -210 \ kJ$ and $\Delta S = -150 \ J \ K^{-1}$. Find the temperature so that $\Delta G = 0$. (in $K$)