Association of protons with oxygen-containing molecules in aqueous solution. Part 2.—Protonation of hydroxy-compounds in dilute solution

The equation relating1 concentrations of unprotonated p-nitroaniline in various concentrations of acid, methanol and isopropanol in aqueous solution is shown to apply to hydroxy-compounds in general. The basicity of alcohols at mole fraction<0.02 is influenced by the electronegativity and steric effects of the groups attached to the oxygen atom. The steric effects appear to arise from interference with the distribution of proton affinity by hydrogen bonding within the hydrated oxonium ion caused by the freedom of movement of groups in non-cyclic compounds.