What is the primary use of a buffer solution?

A buffer solution is specifically designed to maintain a stable pH in a system, even when small amounts of acids or bases are added. This characteristic is essential in various biological and chemical processes, where a constant pH is crucial for optimal functioning. Buffers typically consist of a weak acid and its conjugate base (or a weak base and its conjugate acid), which together can resist changes in pH by neutralizing added acids or bases.

For instance, in biological systems such as blood, buffers help regulate pH levels, ensuring that enzymatic reactions and metabolic processes proceed efficiently. This is why maintaining a stable pH is the primary use of buffer solutions, differentiating them from other types of solutions that serve different purposes, such as dissolving solids or enhancing reactions.