The positive value of $\Delta S$ indicates that

Which functions are required to understand the second law of thermodynamics?

An engine operating between $150\,^{\circ}C$ and $25\,^{\circ}C$ takes $500\,J$ of heat from a higher temperature reservoir. If there are no frictional losses,the work done by the engine is.....$J$.

Given $\Delta _rS^o = -266 \ J \ K^{-1}$ and the listed $S_m^o$ values,calculate $S^o$ for $Fe_3O_{4(s)}$ for the reaction: $4 Fe_3O_{4(s)} + O_{2(g)} \to 6 Fe_2O_{3(s)}$. Given $S_m^o(Fe_2O_3) = 87 \ J \ K^{-1} \ mol^{-1}$ and $S_m^o(O_2) = 205 \ J \ K^{-1} \ mol^{-1}$.

For which of the following processes is $\Delta S$ negative?

In which of the following reactions is $\Delta S$ maximum?