Potentiometry titiration

In a potentiometric acid-base titration, an indicator is not necessary. A pH meter is used to measure the pH as base is added in small increments (called aliquots) to an acid solution. A graph is then made with pH along the vertical axis and volume of base added along the horizontal axis

The electrochemical cell consists of two half-cells, each containing an electrode immersed in a solution of ions whose activities determine the electrode's potential

Calomel and silver/silver-chloride electrodes are commonly used in potentiometric titration. In the case of possible interferences of chlorides (as in determination of halides), a mercurous sulfate electrode may be used. In the following series of experiments a home made Ag/AgCl/1 M KCl reference electrode is used.

Potentiometric titration belongs to chemical methods of analysis in which the endpoint of the titration is monitored with an indicator electrode that records the change of the potential as a function of the amount (usually the volume) of the added titrant of exactly known concentration.