Question

The next 11 questions are related to the titration of 40.00 mL of a 0.0850 M acetic acid solution with 0.0700 M KOH. Assume that the temperature is 25 ^oC.

The initial pH of the analyte solution is: 2.91

The volume of KOH required to reach the equivalence point of the titration is: 48.57 mL

Number of mmol of acetate present at the equivalence point:  3.400

The total volume of the solution at the equivalence point: 88.57 mL

The analytical concentration of acetate ions at the equivalence point: 3.839×10^-2 M

The pOH at the equivalence point: 5.33

The pH at the equivalence point: 8.67

The volume of KOH that has been added at the half-equivalence point: 24.29 mL

Tthe pH at the half-equivalence point: 4.76

Part 1 - What is the pH when 20.00 mL of the KOH solution have been added?

Hint:

This is essentially a buffer solution so use Henderson-Hasselbalch equation.

Part 2 - What is the pH when 59.00 mL of the KOH solution have been added?

Hint:

Since you are past the equivalence point, this is an excess base solution. The pH will be determined by the moles of base added after the equivalence point and the total volume of the solution.

I am stuck on the last two parts of this question, I provided the answers to the other parts of the question and the hints for the last two parts. Please help and please show work!

Answer 1