A weak base has an [OH-] = 3.7 x 10-5 M. Calculate the [H3O+]. Note: Kw = [OH-] x [H3O+] = 1.0 × 10–14

Question

A weak base has an [OH-] = 3.7 x 10-5 M. Calculate the [H3O+]. Note: Kw = [OH-] x [H3O+] = 1.0 × 10–14

Answer 1

From the relationship that [OH^-][H₃O⁺] = 1.0x10^-14, we can find one when given the other.

We are given [OH^-] = 3.7x10^-5, so it is easy to find [H₃O⁺].

3.7x10^-5 (H₃O⁺) = 1.0x10^-14

H₃O⁺ = 1.0x10^-14 / 3.7x10^-5

H₃O⁺ = 2.7x10^-10 M