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The process of cation renewal, which takes place on a cathode with a

negative potential, is called the cathode process, and the process of anions

oxidation that occurs on an anode having a positive potential is the anode process.

The course of these processes depends on many factors: the nature of the oxidizer

and the reducing agent, the ions concentration, temperature, nature of the

electrodes, solvent, etc.

Almost all easily oxidized metals (Sodium, Potassium, Calcium, etc.) are

obtained by electrolysis of their molten salts or bases. It should be taken into

consideration that during electrolysis the anode material may be oxidized.

Therefore the electrolysis with an inert and an active anode is distinguished. The

anode whose material is not oxidized during the electrolysis is called inert. The

anode the material of which is capable of oxidizing during the electrolysis is called

active. Most inert anodes are made of Graphite and Platinum. Let us analyze the
processes that occur during electrolysis with inert electrodes.

1 Electrolysis of molten substances
During the passage of an electric current through a molten substance, for example,

NaCl salts, Na + cations move to a negatively charged electrode, where they are
restored, interacting with electrons entering the external circle:

+
Na + 1 ē = Na.

-
Anions Сl move to a positively charged electrode, where they are oxidized,

giving excess electrons away:
–
2 Сl – 2 ē = Сl 2.

As a result, we get two products: there is metallic sodium on a cathode, and

gaseous chlorine on an anode. Consequently, the total equation of the oxidation-

reduction reaction occurring during the electrolysis of the molten NaCl will be as

follows:
–
+
2Na + 2 Сl = 2Na + Сl 2.

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