Hydrochloride

In chemistry, hydrochlorides are salts resulting, or regarded as resulting, from the reaction of hydrochloric acid with an organic base (mostly amine).

For example, reaction of pyridine (C₅H₅N) with hydrochloric acid (HCl) yields pyridine hydrochloride (C₅H₅N.HCl). Even though, this style of formulas is often used for denoting the hydrochlorides, the dot between both parts would mean it is 1:1 mixture, or two molecules weakly bonded together, which is not true. It is the salt C₅H₅NH⁺ Cl^- with correct chemical name pyridinium chloride.

Converting otherwise water-insoluble amines into hydrochlorides is a common way to make them water-soluble. Many pharmaceutical substances are used as hydrochlorides.