What is the [H3O+] (molarity) of a 0.1250 M ethanolamine?

HOC2H4NH2 + H2O ↔ HOC2H4NH3+ + OH- Kb = 3.20e-5

[OH-] = SQRT(0.1250 * 3.20e-5) = 4.00 x 10^-6 M

Kw = [H+] [OH-]

1.00 x 10^-14 = [H+] (4.00 x 10^-6)

[H+] = 2.50 x 10^-9 M

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