Match the following descriptions of titration curves with the diagrams: (d) strong base added to polyprotic acid. [Section 17.3]

Key Concepts

Titration Curves

Titration curves graphically represent the pH changes that occur during the titration of an acid or base. They illustrate how the pH of a solution changes as a titrant is added, showing distinct regions such as the initial pH, buffer regions, and equivalence points. Understanding these curves is essential for interpreting the behavior of acids and bases during titration.

Polyprotic Acids

Polyprotic acids are acids that can donate more than one proton (H+) per molecule in a stepwise manner. Each dissociation step has its own equilibrium constant, leading to multiple equivalence points in a titration curve. Recognizing the characteristics of polyprotic acids is crucial for predicting the shape of their titration curves and understanding the pH changes at each stage.

Equivalence Point

The equivalence point in a titration is the stage at which the amount of titrant added is stoichiometrically equivalent to the amount of substance being titrated. At this point, the reaction between the acid and base is complete, resulting in a significant change in pH. Identifying the equivalence point is vital for determining the concentration of the unknown solution and interpreting the titration curve accurately.