In a particular reaction, 4 kJ heat is released by the system and 12 kJ work done on the system. Calculate the $\Delta H$ and $\Delta U$.

Which of the following relations is correct for a reaction $\text{S}_{(s)} + \text{O}_{2(g)} \rightarrow \text{SO}_{2(g)}$ ?

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