Dissociation in
chemistry and
biochemistry is a general process in which molecules (or ionic compounds such as
salts, or
complexes) separate or split into smaller particles such as atoms, ions or
radicals, usually in a reversible manner. For instance, when an
acid dissolves in water, a
covalent bond between an
electronegative atom and a hydrogen atom is broken by
heterolytic fission, which gives a proton (H
+) and a negative
ion. Dissociation is the opposite of
recombination.