Calculate the pH of a solution in which [OH-] = 4.5 * 10-9M.

8.35

6.11

4.94

5.65 - this one is correct

5.65 is the pH.

Explanation:

I am assuming that you are asking for confirmation on your answer. The answer is 5.65.

You would do:

[pOH] = - log[OH-]

= - log[4.5*10^-9]

equals about 8.3468

To find pH your would subtract the pOH from 14.

14-8.3468 = 5.65 << Rounded to match the answer choices.