Buffer Solutions

Buffer Solutions

Adding as little as 0.1 mL of concentrated HCl to a liter of H2O shifts the pH from

7.0 to 3.0. The same addition of HCl to a liter solution that is 0.1 M in both a weak

acid and its conjugate weak base, however, results in only a negligible change in pH.

Such solutions are called buffers, and their buffering action is a consequence of the

relationship between pH and the relative concentrations of the conjugate weak

acid/weak base pair A mixture of acetic acid and sodium acetate is one example of an acid/base buffer.