The effect of alkyl substitution on alcohol acidity is due primarily to solvation of the alkoxide ion that resuls from dissociation. The more esily the alkoxide ion is solvated by water, the more stable it is, the more its formation is energetically favored, and the greater the acidity of the parent a lcohol. For example, the oxygen atom of an unhindered alkoxide ion, such as that from methanol, is sterically accessible and is easily solvated by water. The oxygen atom of a hindered alkoxide ion, however, such as that from tert-butyl alcohol, is less easily solvated and is therefore less stabilized.