The base dissociation equilibrium constant (Kb) for C5H5N is 1.40×10-9 (eq. 1).

Question

(eq. 1): C5H5N(aq) + H2O(l) = OH-(aq) + C5H5NH+(aq)

Calculate the value of the equilibrium constant (Ka) for the hydrolysis of C5H5NH+ as shown in the reaction (eq. 2).

(eq. 2): C5H5NH+(aq) + H2O(l) = H3O+(aq) + C5H5N(aq)

sorry for so many questions

Answer 1

Ka = (Kw/Kb).
Just remember that KaKb = Kw. The Ka and Kb are interchangeable with that formula.