Which characteristic of weak electrolytes is determined by the acid dissociation constant Ka?

The acid dissociation constant, denoted as Ka, is a quantitative measure of the strength of an acid in solution. It specifically reflects the extent to which an acid can donate protons (H⁺) to water, meaning it indicates how far the dissociation of the weak acid will go.

For weak electrolytes, which only partially dissociate in solution, the value of Ka directly correlates with their extent of dissociation. A larger Ka value indicates a greater tendency to dissociate into protons and conjugate bases, suggesting a stronger weak acid. Conversely, a smaller Ka value signifies limited dissociation. Thus, the Ka value is crucial for understanding how much of the weak electrolyte ionizes in solution, leading to the conclusion that the correct answer relates to the extent of dissociation.

Other characteristics, such as solubility, molecular weight, and boiling point, are influenced by different factors. For example, solubility might relate to other chemical properties, and molecular weight does not directly pertain to dissociation phenomena. Boiling point is primarily impacted by intermolecular forces rather than the degree of ionization of an acid in solution. Therefore, while these other factors are important in the broader context of physical chemistry, they are not determined