Chemistry: Molecular Approach (4th Edition)

Diprotic and triprotic acids are types of polyprotic acids, meaning that they ionize in successive steps (at least two), having a different $K_a$ for each different step. Diprotic acids contain two ionizable protons, having two successive steps of ionization, and triprotic acids contain three ionizable protons and three successive steps of ionization. Example of Diprotic acid: $H_2SO_4$ Example of Triprotic acid: $H_3PO_4$
Diprotic and triprotic acids are types of polyprotic acids, meaning that they ionize in successive steps (at least two), having a different $K_a$ for each different step. Diprotic acids contain two ionizable protons, having two successive steps of ionization, and triprotic acids contain three ionizable protons and three successive steps of ionization. Example of Diprotic acid: $H_2SO_4$ Example of Triprotic acid: $H_3PO_4$