8.4 Acid-Base Reactions and Buffers

Buffers

When ${H^+}$ and {OH^–} ions are added to a solution, the pH is subject to change. However, a solution with a type of equilibrium known as a buffer solution is able to resist these changes to pH to a certain degree.

A buffer solution simply consists of two components: a weak acid and its conjugate base. For example, a buffer could consist of HF, and its conjugate base {F^–}. These two, in approximately equal concentrations, will exist in equilibrium with each other (as in a weak acid, it will not fully dissociate). When ${H^+}$ is added, it will react with the {F^–} to form ${HF}$, and the pH will not be drastically impacted. Similarly, any {OH^–} added will react with the ${HF}$, and the pH will still be unaffected.