CHEMISTRY COMMUNITY

What is a buffer and how is it made?

Buffers are solutions that when an acid or a base is added to the solution, it does not affect the pH. Buffers are usually made by adding a weak acid with its salt in water.

The purpose of a buffer is to resist PH changes in a solution, helping to keep the solution's PH constant despite additions of acids or bases. A buffer can be made from a weak acid or a weak base and their respective salts, or from a combination of 2 salts that form a conjugate acid-base pair.

The effectiveness of buffers comes from their ability to both accept protons from any acids added, as well as donating protons to any base added, so that water is unaffected and the concentrations of H+ and OH- stay relatively constant.