Water is an amphoteric compound that also acts as a good solvent of polar and ionic compounds. The three physical states of $$\(\mathrm{H}_{2} \mathrm{O}\)$$ have different standard entropies, $$\(S^{\ominus}\)$$, associated with them. Table 2.1 shows these $$\(S^{\theta}\)$$ values. (i) Explain the difference in the $$\(S^{\ominus}\)$$ values of $$\(\mathrm{H}_{2} \mathrm{O}(\mathrm{s})\)$$ and $$\(\mathrm{H}_{2} \mathrm{O}(\mathrm{l})\)$$. ....................................................................................................................................... . ................................................................................................................................. (ii) Explain why the increase in $$\(S^{\theta}\)$$ is much greater when $$\(\mathrm{H}_{2} \mathrm{O}\)$$ boils than when it melts. ....................................................................................................................................... . ................................................................................................................................. (iii) The energy changes for $$\(\mathrm{H}_{2} \mathrm{O}(\mathrm{s}) \rightarrow \mathrm{H}_{2} \mathrm{O}(\mathrm{I})\)$$ are shown. $$\[ \begin{aligned} & \Delta G=0.00 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ & \Delta H=+6.03 \mathrm{~kJ} \mathrm{~mol}^{-1} \end{aligned} \]$$ Use these data to show that the melting point of $$\(\mathrm{H}_{2} \mathrm{O}(\mathrm{s})\)$$ is $$\(0^{\circ} \mathrm{C}\)$$.

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