Explain the variations in solubility in water of the alcohols listed here:
$$
\begin{array}{lc}
\hline \text { Compound } & \begin{array}{c}
\text { Solubility in Water } \\
(\mathrm{g} / \mathbf{1 0 0} \text { g }) \text { at } \mathbf{2 0 ^ { \circ }} \mathbf{C}
\end{array} \\
\hline \mathrm{CH}_3 \mathrm{OH} & \infty \\
\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{OH} & \infty \\
\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{CH}_2 \mathrm{OH} & \infty \\
\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{CH}_2 \mathrm{CH}_2 \mathrm{OH} & 9 \\
\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{CH}_2 \mathrm{CH}_2 \mathrm{CH}_2 \mathrm{OH} & 2.7 \\
\hline
\end{array}
$$