The pOH Scale
The pOH scale is the corollary of the pH scale.
 
ie. pH + pOH = 14 You'll remember from math class that when you multiply two numbers you only add their logs.
 
[H3O+] = (1.0 x 10-7 )*(1.0 x 10-7) = 1.0 x 10-14
or
-log[H3O+] = 7 + 7 = 14
 
Thus a solution that has a pH = 7 must also have a pOH = 7.
 
What is the pOH of a 0.010 mol/L NaOH solution?
 
What is it's pH?
 
What are the hydronium ion and hydroxide ion concentration of a solution prepared by adding 1 mL of 1.0 mol/L HCl to 9 mL of water? Assume that volumes are additive and that the 1 mol/L HCl dissociates completely.
 
Follow-up problems
What are the hydronium ion and hydroxide ion concentrations of a solution made by adding 1 mL of 0.1 mol/L NaOH to 9 mL of water?
 
Find the pH, pOH, [OH-] of a 0.00010 mol/L HCl solution.
 
Find the pH of a 0.00325 mol/L NaOH solution.
 
What is the hydronium ion concentration of a solution that has a pH = 2.6?
            Go to the Acid-Base Water,  pH,  and pOH Worksheet