Schematic Diagram of a Potentiometric Electrochemical Cell

Shown here is the schematic diagram of a typical potentiometric electrochemical cell. The electrochemical cell consists of two half-cells, each consisting of an electrode immersed in a solution of ions whose activities determine the electrode’s potential. A salt bridge containing an inert electrolyte, such as KCl, connects the two half-cells. The ends of the salt bridge are fixed with porous frits, allowing the electrolyte’s ions to move freely between the half-cells and the salt bridge. This movement of ions in the salt bridge completes the electrical circuit.