Question

which of the following is true at the equivalence point in a weak acid/weak base titration? select one: the ph is equal to pka of the weak acid. the moles of acid are equal to the moles of base. the concentration of acid is equal to the concentration of base. the volume of acid is equal to the volume of base.

Answer 1

The answer is that at the equivalence point in a weak acid/weak base titration, the moles of acid are equal to the moles of base. This point does not necessarily correspond to a pH that is equal to the pKa of the weak acid; that occurs at the titration's midpoint.

Step-by-step explanation:

The correct statement regarding the equivalence point in a weak acid/weak base titration is that the moles of acid are equal to the moles of base. At the equivalence point in a titration, the moles of the titrant added from the burette (acid or base) are stoichiometrically equivalent to the moles of the substance being titrated (base or acid). In the context of weak acid/weak base titrations, the pH at the equivalence point is not necessarily 7.0 as it is for strong acid/strong base titrations, and it does not necessarily equal the pKa of the weak acid. However, at the midpoint of the titration, which is different from the equivalence point, the pH is indeed equal to the pKa of the weak acid.