1. The problem statement, all variables and given/known data A 50.0 mL sample of a 1.00 M solution of a diprotic acid H2A (Ka1 = 1.0 × 10–6 and Ka2 = 1.0 × 10–10) is titrated with 2.00 M NaOH. What is the minimum volume of 2.00 M NaOH needed to reach a pH of 10.00? (A) 12.5 mL (B) 37.5 mL (C) 25.0 mL (D) 50.0 mL 2. Relevant equations pH=-log[H+] 3. The attempt at a solution I believe I am missing something extremely obvious. I find that NaOH, being a strong base will completely neutralize the acid and then additional base will be required to have the pH reach 10.00. So I found moles of hydrogen, being .05*1.00.*2. I then divided by molarity of the NaOH to find volume of NaOH required to completely neutralize it, and find 50.0 mL. Now this is where I get confused. D is the highest answer, and only has enough base to neutralize the acid, not to dissociate and to increase pH.