Question

What is the pH of a 0.77M solution of methylamin at 25 degree C? CH3NH2, Kb= 4.4X10-4?

How do I set this up to get the answer?

Answer 1

Here is the ICE table.
........CH3NH2 + HOH ==> CH3NH3^+ + OH^-
I.......0.77...............0.........0
C.........-x...............x.........x
E........0.77-x............x.........x

Substitute the E line into the Ka expression and solve for x= OH^-, then convert to H^+ and pH.