Which of the following reactions has a positive entropy change?

The entropy change when $2 \, \text{moles}$ of an ideal monoatomic gas is heated from $200 \, ^\circ \text{C}$ to $300 \, ^\circ \text{C}$ isochorically is:

In which of the following processes does entropy increase?
$A$. $A$ liquid evaporates to vapour.
$B$. Temperature of a crystalline solid is lowered from $130 \ K$ to $0 \ K$.
$C$. $2 NaHCO_{3(s)} \rightarrow Na_2CO_{3(s)} + CO_{2(g)} + H_2O_{(g)}$
$D$. $Cl_{2(g)} \rightarrow 2 Cl_{(g)}$
Choose the correct answer from the options given below:

What happens to the entropy of water when it freezes to form an ice cube?

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 $J \ K^{-1}$)?

One mole of which of the following has the highest entropy?