Among the following processes,for which process is the change in entropy $(\Delta S)$ negative?

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 $27 \, ^oC$.

The entropy change involved in the conversion of $1 \, \text{mole}$ of liquid water at $373 \, K$ to vapour at the same temperature will be $[\Delta H_{vap} = 2.257 \, kJ/g]$. (in $, kJ/K$)

In a reversible expansion,one mole of gas is expanded isothermally at $200 \ K$ till its volume increases $10$ times. Calculate $\Delta S_{total}$ at equilibrium (in $J \ K^{-1}$)?

In which state does matter have the highest entropy?

What is entropy?