Starting with an aqueous solution of 115 mL of 0.35 M pyridine (Kb = 1.7 x 10-9), determine the observed pH of the solution at the following points in a titration:
At the beginning
After the addition of 100 mL of 0.20 M HCl
At the equivalence point (adding only 0.20 M HCl to neutralize)
After the addition of 325 mL of 0.20 M HCl (to the original solution)