Exhibit 3B A titration curve.
Refer to Exhibit 3B.Which points on the graph represent pK's?

Question

Exhibit 3B  A titration curve.
Refer to Exhibit 3B.Which points on the graph represent pK's?

Quizplus · Accepted Answer

The points on the graph that represent pK's are the inflection points on the curve where there is a significant change in pH with the addition of small amounts of titrant. These inflection points occur at pH values that correspond to dissociation equilibria, which are the protonation or deprotonation of functional groups on the molecule being titrated. In the given titration curve, there are three such inflection points at pH values of approximately 2.2, 4.8 and 9.6, which correspond to the dissociation of the carboxylic acid group (pK1), the amino group (pK2), and the side-chain carboxylic acid group (pK3) of an amino acid, respectively. Therefore, the best choice is B, which includes all three inflection points.

Exhibit 3B a Titration Curve