Question

Ascorbic acid (vitamin C, C6H8O6) is a diprotic acid (Ka1 = 8.0×10^–5 and Ka2 = 1.6×10^–12). What is the pH of a 0.240 M solution of ascorbic acid?

Answer 1

Explanation:

We are given: Ka1 = 8.0*10^-5

: Ka2 = 1.6*10^-12

: concentration = 0.240M

The value of Ka1>>Ka2, therefore Ka2 will not be considered in this calculations.

We then determine the concentration of H+ at equilibrium.

Let [C6H6O6-] = x, [H+] = x