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The ChemCollective >> Buffer Review >>Definitions

Review of Buffers


pH is a measure of the concentration of H+ [H3O+] ions in a solution. Only the concentration of H+ and OH- molecules determine the pH. When the concentration of H+ and OH- ions are equal, the solution is said to be neutral. If there are more H+ than OH- molecules the solution is acidic, and if there are more OH- than H+ molecules, the solution is basic.


To be able to add a strong acid or base to a solution without causing a large change in the pH, we need to create a buffer solution. A buffer solution contains both a weak acid (HA) and its conjugate base (A-).


   Page Last Updated: 06.30.2006