Hydroxy compounds as acids and bases

Compounds containing the group -OH constitute the largest category of acids, especially if the organic acids (discussed separately farther on) are included. M-OH compounds also include many of the most common bases. 

Whether a compound of the general type M-O-H will act as an acid or a base depends in the final analysis on the relative strengths of the M-O and the O-H bonds. If the bond is weaker, then the -OH part will tend to retain its individuality and will act as a hydroxide ion. If the O-H bond is weaker, the MO- part of the molecule will remain intact and the substance will be acidic. 

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