The pH at the equivalence point will be approximately equal to the average of these two pH values, (1.85 + 7.19) ÷ 2 = 4.52. 5. The pH at the second equivalence point will be determined by the concentration of SO32-, the conjugate base of the weak acid, HSO3-.Click to see full answer. In this regard, what is the pH at the second equivalence point?The pH at the second equivalence point is 8.90.One may also ask, what’s the pH at the equivalence point? At the equivalence point, the pH = 7.00 for strong acid-strong base titrations. However, in other types of titrations, this is not the case. People also ask, how do you find the pH at the equivalence point of a titration? In the case of titration of weak acid with strong base, pH at the equivalence point is determined by the weak acid salt hydrolysis. That means we have to find pKb of conjugated base and calculate concentration of OH- starting from there, then use pH=14-pOH formula.What is the pH at the first equivalence point? about 5