Question

Pyridine, a substance used as a catalyst in some synthetic reactions is a very weak base its degree of ionization is equal to 0.03% in solution
0.02 mol L -¹. Determine the ionization constant.

Answer 1

Let;s call pyridine just B and we know that is a base.
............B + HOH ==> BH^+ + OH^-
I........0.02........0.02*0.0003 for BHY and 0.02*0.0003 for OH.

Substitute that into the Kb and solve for Kb.