What does the Henderson-Hasselbalch equation explain?

The equation explains the quantitative relationship between the pH of a solution and the ratio of the concentrations of a weak acid and its conjugate base. It illustrates how the pH of a buffer solution depends on the acid-base equilibrium and how changes in the ratio of [A⁻]/[HA] affect the pH. This understanding is fundamental in acid-base chemistry and the design of buffer systems.