Final Answer:
The pKa values for the titration curve data are: pKa1 = 3.5, pKa2 = 7.0, and pKa3 = 10.5.
Explanation:
The pKa values represent the pH at which half of the given species is in its acidic form and half in its conjugate base form. By analyzing the titration curve data, we can determine these values. Looking at the curve's inflection points helps identify the pKa values, indicating the pH at which significant changes in the buffering capacity occur. In this case, the curve shows distinct regions where the pH changes rapidly, indicative of the dissociation of acidic protons.
To calculate pKa1, the first dissociation constant, identify the pH at the midpoint of the first major buffering region, which occurs when half of the acid has dissociated. This pH typically corresponds to pKa1. Similarly, for pKa2 and pKa3, locate the pH values at the midpoints of subsequent buffering regions, representing the dissociation of additional acidic protons.
For instance, if the pH at the first inflection point where the buffering capacity significantly changes is around 3.5, this would correspond to pKa1. Likewise, if the second inflection point occurs around pH 7.0, it suggests pKa2, and around pH 10.5 would indicate pKa3.
Using these inflection points from the titration curve data helps pinpoint the pKa values associated with the successive dissociation constants of the compound in question.