What is the role of buffers in a solution?

Buffers play a crucial role in maintaining the pH level of a solution by neutralizing small amounts of acids or bases that may be added. They are typically composed of a weak acid and its conjugate base or a weak base and its conjugate acid. This composition allows buffers to react with added acids or bases to minimize changes in pH. When an acid is introduced to a buffered solution, the weak base component of the buffer can react with the hydrogen ions (H+) from the acid to neutralize it. Conversely, if a base is added, the weak acid in the buffer can donate protons (H+) to counteract the increase in hydroxide ions (OH-), thereby stabilizing the pH.

Buffers are essential in biological systems where many biochemical processes require a stable pH to function properly. For instance, human blood contains buffers that help maintain its pH around 7.4, which is critical for normal physiological functions.