In which state does matter have the highest entropy?

Ice at $-5^{\circ} C$ is heated to become vapor with a temperature of $110^{\circ} C$ at atmospheric pressure. The entropy change associated with this process can be obtained from:

In which of the following processes does entropy decrease?

Given the standard entropy values at $298 \ K$ and $1 \ atm$ as $H_2(g) : 130.6 \ J \ K^{-1} \ mol^{-1}$,$Cl_2(g) : 223.0 \ J \ K^{-1} \ mol^{-1}$,and $HCl(g) : 186.7 \ J \ K^{-1} \ mol^{-1}$,calculate the entropy change $(\Delta S^{\circ})$ in $J \ K^{-1} \ mol^{-1}$ for the reaction: $H_2(g) + Cl_2(g) \rightarrow 2HCl(g)$

The standard entropies of $CO_{2(g)}$,$C_{(s)}$,and $O_{2(g)}$ are $213.5$,$5.740$,and $205 \ J \ K^{-1} \ mol^{-1}$ respectively. The standard entropy of formation of $CO_{2(g)}$ is $...... \ J \ K^{-1} \ mol^{-1}$.

What is the change in entropy when an ideal gas expands into a vacuum?