posted by Kasey .
What ratio [CH3NH3+]/[CH3NH2] is needed to prepare a buffer solution with a pH of 8.60 from methylamine, CH3NH2, and methylammonium chloride, CH3NH3Cl? Kb of CH3NH2 = 3.7e-4.
pH = pKa + log(base/acid)
Subsitute pH, convert pKb to pKa and calculate the ratio of base/acid and reverse that since you want the ratio of acid to base.