A diprotic acid, H₂A, has the following dissociation constants:
K_a1 = 2.1 x 10^-7 and K_a2 = 4.3 x 10^-13. The H₃O⁺ ion concentration when this acid is dissolved in water is

Question

A diprotic acid, H₂A, has the following dissociation constants: K_a1 = 2.1 x 10^-7 and K_a2 = 4.3 x 10^-13. The H₃O⁺ ion concentration when this acid is dissolved in water is

Quizplus · Accepted Answer

Given the dissociation constants (Ka1 = 2.1 x 10^-7 and Ka2 = 4.3 x 10^-13), the first dissociation is much more significant than the second. Therefore, the concentration of HSO4^- (from the first dissociation) will be approximately equal to the concentration of HASO4^2- (from the second, much less significant dissociation).

A Diprotic Acid, H2A, Has the Following Dissociation Constants

A Diprotic Acid, H₂A, Has the Following Dissociation Constants