The dibasic compound B (pKb1 = 4.00, pKb2 8.00) was titrated with 1.00 M HCl. The initial solution of B was 0.100 M and had a volume of 100.0 mL. Find the pH at the following volumes of acid added and make a graph of pH versus Va: Va 0, 1, 5, 9, 10, 11, 15, 19, 20, and 22 mL.