1) A 0.70 M solution of a weak acid, HA, has a pH of 3.72. What is the percentage ionization of the acid? What is the value of Ka for the acid? 2) Periodic acid, HIO4, is an important oxidizing agent and a moderately strong acid. In a 0.20 M solution, [H+] = 5.7 × 10-2 mol L-1. Calculate Ka and pKa for periodic acid.