For a certain reaction,the enthalpy change and entropy change are $40.63 \ kJ \ mol^{-1}$ and $100 \ J \ K^{-1} \ mol^{-1}$ respectively. What will be the value of $\Delta G$ at $27 \ ^oC$?

For the reaction $CaCO_{3(s)} \to CaO_{(s)} + CO_{2(g)}$,given $\Delta H^o = 178.3 \, kJ$ and $\Delta S^o = 160 \, J \cdot K^{-1}$. At what temperature will the reaction become spontaneous?

For a reaction to be spontaneous at all temperatures, the values of enthalpy change $\Delta H$ and entropy change $\Delta S$ should be:

For the reaction at $298 \, K$,$2 A + B \rightarrow C$. Given $\Delta H = 400 \, kJ \, mol^{-1}$ and $\Delta S = 0.2 \, kJ \, K^{-1} \, mol^{-1}$. At what temperature will the reaction become spontaneous,considering $\Delta H$ and $\Delta S$ to be constant over the temperature range?

Describe Gibbs energy and spontaneity.

An enthalpy diagram for a particular reaction is given in the figure. Is it possible to decide the spontaneity of a reaction from the given diagram? Explain.