A 0.37 M solution of a weak base B has a pH of 9.12. The equation for ionization is
B (aq) + H2O → BH+ + OH-

What are the BH+
, OH-
, and B concentrations at equilibrium? Calculate Kb
for the base.

Question

A 0.37 M solution of a weak base B has a pH of 9.12. The equation for ionization is 
B (aq) + H2O → BH+ + OH-
 
What are the BH+
, OH-
, and B concentrations at equilibrium? Calculate Kb
 for the base.

aaronq · Answer

you can write an equilibrium expression for the dissociation, then use pH to find [OH^-], use it to find the equilibrium concentrations and Kb.