Final answer:
In the titration of a polyprotic acid, the successive equivalence point volumes are determined by the number of protons remaining in the acid and their respective acid dissociation constants. Each stage of the neutralization reaction corresponds to the titration of a proton. The volume of base required to reach each equivalence point increases as the acid is deprotonated and fewer protons remain.
Step-by-step explanation:
The relationship of the successive equivalence point volumes in the titration of a polyprotic acid can be explained by understanding the neutralization reaction that occurs. When a strong base is added to a solution of a polyprotic acid, the neutralization reaction occurs in stages. The most acidic group is titrated first, followed by the next most acidic group, and so on.
Each stage of the neutralization reaction corresponds to the titration of a proton. The volume of base required to reach each successive equivalence point is determined by the number of protons remaining in the acid and their respective acid dissociation constants (pKa values).
The titration curve for a polyprotic acid will show distinct steps, where each step corresponds to the titration of a proton. These steps will be well-resolved if the pKa values for each proton are separated by at least three pKa units. The volume of base required to reach each equivalence point will increase as the acid is deprotonated and fewer protons remain.