Chapter 16: Acid–Base Equilibria

Students learn that the autoionization of water generates hydronium and hydroxide ions in equilibrium, characterized by the ion-product constant Kw, which enables calculation of pH and pOH values central to quantifying acidity. The distinction between strong acids and bases, which dissociate completely in solution, and weak acids and bases, which establish partial dissociation equilibria, introduces the acid dissociation constant Ka and base dissociation constant Kb as measures of molecular strength. Computational methods using ICE tables systematically determine equilibrium concentrations, degree of ionization, and pH for weak acid and weak base systems. Polyprotic acids undergo stepwise dissociation with distinct Ka values for each ionization step, requiring sequential analysis of proton removal. Salt hydrolysis demonstrates how the ionic constituents of dissolved salts can alter solution pH through hydrolysis reactions of cations and anions. The relationship between molecular structure, electronegativity, and acid strength reveals why certain compounds donate protons more readily than others. Throughout the chapter, students develop the ability to predict equilibrium positions, connect structural properties to observable chemistry, and apply these principles to biological and industrial systems where acid-base chemistry governs reaction feasibility and mechanism.