For an endothermic reaction $A \rightarrow B$ to occur spontaneously at a constant temperature $T$,the entropy change $\Delta S$ must be:

What is the entropy change (in $J\, K^{-1}\, mol^{-1}$) when one mole of ice is converted into water at $0^{\circ}C$? (The enthalpy change for the conversion of ice to liquid water is $6.0\, kJ\, mol^{-1}$ at $0^{\circ}C$)

What is the change in entropy when an ideal gas expands into a vacuum?

For the reaction $A + B \rightarrow C + D + q$,which has a positive entropy change,the reaction:

Ice at $-5^{\circ} C$ is heated to become vapor with a temperature of $110^{\circ} C$ at atmospheric pressure. The entropy change associated with this process can be obtained from:

For a process to be spontaneous,the total entropy change of the system and its surroundings must be $ \Delta S_{total} > 0 $. This condition is characteristic of which type of process?