Question

The half-equivalence point of a titration occurs half way to the end point, where half of the analyte has reacted to form its conjugate, and the other half still remains unreacted. If 0.220 moles of a monoprotic weak acid (Ka = 5.7 × 10-5) is titrated with NaOH, what is the pH of the solution at the half-equivalence point?

Answer 1

pKa=-log(Ka)
Then to find pH use, pKa+log(0.220/0.220)
Thus, pH=pKa