Capillary electrolytic half-cell

Let us consider the voltage first. When a metal electrode M (— the electrode whose interface with the solution we investigate henceforth referred to the woi k-ing electrode is dipped into an electrolyte solution and equilibrium is established, an electrostatic potential is established between the two phases. What is usually measured (see Fig. 17.1) is the potential difference between this electrode and a reference half cell, R—say a platinum electrode in contact with some fixed redox solution which in turn is connected by a capillary to the close neighborhood of... 

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