Question

Diethylamine, (C2H5)2NH, is a weak base with Kb = 6.92×10−4 at 25 oC.
For a 0.133 mol L−1 solution of (C2H5)2NH at 25 oC, what is the percent ionization of (C2H5)2NH?

Answer 1

Let's call (C2H5)2NH simply BH.
...........BH + HOH ==> BH2 + OH^-
I..........0.133..................0...........0
C.........-x.........................x...........x
E.....0.133-x.....................x...........x
Plug the E line into the Kb expression and solve for x = (OH^-). Convert to pH. Post your work if you get stuck.

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