What is the pH of a solution which has hydroxide concentration, [OH-], equal to 7.6 x 10-4 M?
0.88
3.12
10.9
13.1
none of the above
I had chose 3.12 for this one and this one was also wrong. I did this because I did the equation -log(7.6*10^-4) and got 3.12.
You calculated the pOH. The question asks for pH. After you have pOH, then
pOH + pH = pKw = 14. You know pKw and pOH, solve for pH.