Dropping Mercury Electrode advantages

One of the outstanding advantages of the mercury cathode is that the optimum control potential for a given separation is easily determinable from polarograms recorded with the dropping mercury electrode. This potential... 

What are two advantages of the dropping mercury electrode over a stationary electrode ... 

The first hydrodynamic electrode to be invented was the dropping mercury electrode [1]. It has a cyclic operation and can thus be considered only as quasi-steady-state its hydrodynamic character derives from drop growth. The principal advantage of a dropping electrode is that a fresh electrode surface is constantly exposed to the solution however, there are few electrode materials available and mathematical solution of the mass transport to the drop surface is complicated by the fact that the surface is expanding. 

Tire dropping mercury electrode has been studied extensively. Its greatest advantage is that it represents a highly reproducible, clean... 

The dropping mercury electrode has two main advantages when used... 

Polarography is the term used for voltammetry with the dropping mercury electrode (DME). The technique has been discussed extensively in several textbooks and reviews [1-, 237-242] to which the reader is referred for details concerning both theoretical problems and practical applications. The electrode (Fig. 31) was developed early in the century by Heyrovsky and was the dominating tool in electroanalytical chemistry for several decades. Because of the low oxidation potential of mercury (0.3-0.4 V versus SCE), the DME has been used almost exclusively for the study of reduction processes. Compared with mercury film electrodes, the DME offers the advantage that the electrode surface is continuously renewed. This property reduces undesirable surface effects caused by adsorption. 

List the advantages and disadvantages of the dropping mercury electrode compared with platinum or carbon electrodes. 

An advantage of carbon electrodes is that they are not troubled by oxide formation on the surface, as platinum electrodes are. While carbon electrodes can be used at fairly negative potentials, a dropping mercury electrode (DME) is often preferred because better reproducibility can be achieved. This is because the electrode surface is constantly renewed (small mercury drops fall from a capillary attached to a mercury reservoir). Voltammetric techniques using a dropping mercury electrode are called polarography. 

You will be introduced to the role of solvent, pH, and complexa-tion in polarography, to permit an intelligent choice of a suitable supporting electrolyte for a given analytical problem. The use and advantages of electrodes other than the dropping mercury electrode will be considered. 

Today the term polarography is exclusively used for voltammetry at a dropping mercury electrode (or DME). The advantages of this unique electrode have already been described (Part 1). The drop-... 

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