Chapter 16, Problem 16.43CP

The following pictures represent solutions at various stages in thetitration of a weak diprotic acid ${\text{H}}_{\text{2}}\text{A}$ with aqueous NaOH. ( ${\text{Na}}^{+}$ ions and water molecules have been omitted for clarity)

(a) To which of the following stages do solutions 1—4 correspond?

(i) Halfway to the first equivalence point

(ii) At the first equivalence point

(lii) Halfway between the first and second equivalence points

(iv) Beyond the second equivalence point

(b) Which solution has the highest pH? Which has the lowestpH?