1. What is the pH of a solution whose [H3O+] is 1 X 10 -5 M?

2. What is the [H3O+] concentration of a solution with a pH of 9?

3. What is the pH of a solution whose [H3O+] concentration is 3 X 10-3 M?

4. What is the pH of a solution with a [H3O+] concentration of 1 X 10 -12 M?

5. What is the [H3O+] concentration of a solution whose pH is 8.9?

1 answer

pH = -log(H3O^+)
(H3O^+)(OH^-)= Kw = 1E-14
These two (or their reverses) will work all of these.