Which of the following is the least $random$ state of water?

Which of the following compounds has the highest standard molar entropy?

In which state does matter have the highest entropy?

$STATEMENT-1:$ There is a natural asymmetry between converting work to heat and converting heat to work.
$STATEMENT-2:$ No process is possible in which the sole result is the absorption of heat from a reservoir and its complete conversion into work.

One mole of an ideal gas expands adiabatically and reversibly from its initial pressure to half of its initial pressure. What will be the value of $\Delta S$ in $J \ K^{-1} \ mol^{-1}$? $[\ln 2 = 0.693$ and $R = 8.314 \ J \ mol^{-1} \ K^{-1}]$

For the reaction $MgCO_3(s) \rightarrow MgO(s) + CO_2(g)$,the value of $\Delta S$ is: