Which is more basic? H30 = 2E-5M or -OH = 5E-9M and why?

Question

Which is more basic? H30 = 2E-5M or -OH = 5E-9M and why?

Answer 1

[H+] = (1E-14)/(5E-9) = 2E-6, so that is more basic.

Answer 2

The basic nature of a solution depends on the concentration of OH-

Let's find the [OH-] that corresponds with the concentration of H3O using this formula:

[OH-]*[H3O+] = 1E-14

[OH-](2E-5) = 1E-14

[OH-] = 5E-10

5E-10 is less than 5E-9. Therefore the OH- mentioned in your question is more basic.

Hope I helped :)