veelprotonische
Veelprotonische refers to acids that can donate more than one proton in acid-base reactions. In English, the equivalent term is polyprotic (or polyprotonic) acids. These acids contain several ionizable hydrogens and undergo a series of successive dissociations in aqueous solution, each with its own dissociation constant (Ka1, Ka2, Ka3, …). The general steps can be written as H2A ⇌ H+ + HA−; HA− ⇌ H+ + A2−; HA2− ⇌ H+ + A3−. The magnitudes of the successive pKa values determine the pH ranges over which each proton is released; if the pKa values are well separated, the molecule behaves like a monoprotic acid over broad pH intervals, with distinct buffering around each pKa.
Common examples include sulfuric acid (H2SO4), a diprotic acid with a very strong first dissociation and a
In Dutch-language chemistry, veelprotonische zuren are the standard term for what English texts call polyprotic acids,