For a reversible adiabatic expansion of an ideal gas,which of the following is equal to zero?

For which of the following reactions will $\Delta S$ be maximum?

When the value of entropy is greater,then the ability of work

Calculate the entropy change in $J \, mol^{-1} K^{-1}$ for the isothermal reversible expansion of $2 \, mol$ of an ideal gas from a volume of $10 \, dm^3$ to $100 \, dm^3$ at $27 \, ^oC$.

For an isolated system,$\Delta U = 0,$ what will be $\Delta S?$

For the reaction $NH_4Cl_{(s)} \rightarrow NH_{3(g)} + HCl_{(g)}$,the entropy change is ...... .