Acid-Base Equilibrium: Calculate pH, [OH-] & % Ionization 0.12M N2H4

[Mitchtwitchita]

The base hydrazine, N2H4, has a pKb equal to 5.90. Calculate the hydroxide concentration, the pH, and the % ionization for a 0.12 M solution.

First, is pKb the same as the pOH?

If so, pOH = -log[OH-]
5.90 = -log[OH-]
log[OH-] = -5.90
=10^-5.90
[OH-]=1.26 x 10^-6

pH = 14.00 - pOH
=14.00 - 5.90
=8.10

% ionized = [OH-]/0.12 M X 100% = 0.00105% ?

Somehow I think I'm doing this problem wrong. Can anybody show me what the problem is?

 

[chemisttree]

The base hydrazine, N2H4, has a pKb equal to 5.90. Calculate the hydroxide concentration, the pH, and the % ionization for a 0.12 M solution.

First, is pKb the same as the pOH?

No. pKb is analagous to pKa. It is the negative log of Kb.