A buffer solution is a water-based solution that contains a mixture of a weak acid and its conjugate base, or a weak base and its conjugate acid. Its key characteristic is the ability to maintain a relatively constant pH level even when small amounts of strong acids or bases are added. This resistance to pH change is because the buffer components react with added hydrogen ions (H+) or hydroxide ions (OH-) to neutralize them, thus stabilizing the solution's pH. Buffers are essential in many chemical and biological processes where maintaining a stable pH is crucial.
