deprotonatedsalt

A deprotonated salt is an ionic compound formed when an acid loses a proton to produce its conjugate base, which then combines with a countercation to yield a salt. The term is used descriptively in chemistry, but more precise language often refers to the salt of the conjugate base or an anionic salt.

Formation occurs by deprotonation of an acid (HA) with a base, yielding the conjugate base (A−). The anion then pairs with a metal or other cation (M+) to give the salt MA. Classic examples include sodium acetate (NaCH3COO) derived from acetic acid (CH3CO2H) and methoxide salts such as potassium methoxide (KOCH3) derived from methanol. The equilibrium depends on the acid’s strength (pKa) and the base’s strength.

Properties of deprotonated salts are governed by ionic nature and solubility. In water, they typically dissociate into mobile ions. The anion is usually a relatively basic species and can be protonated back by strong acids; it may also behave as a nucleophile or base in chemical reactions. Some deprotonated salts, particularly alkoxide variants, are highly reactive with water and air, requiring careful handling.

Applications include serving as bases in organic synthesis (for example, methoxide and other alkoxide salts), buffering components in solution, and participating in transesterification and other deprotonation-driven processes. The practical behavior of a deprotonated salt depends on the specific acid, base, and countercation involved as well as the solvent environment.

See also: conjugate base, acid-base reaction, salt, pKa.