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How does electrolysis of molten sodium chloride produce sodium and chlorine?

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combustion — chemical reaction Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.

The electrolysis of molten sodium chloride is a process that uses electric current to drive a chemical change, effectively reversing the formation of the ionic compound sodium chloride.1

In an electrolytic cell, the molten salt—often mixed with calcium chloride to lower its melting point—is subjected to an electric current via two electrodes. The process functions as follows:12

At the Cathode (Negative Electrode): Positively charged sodium ions ( $N a^{+}$ ) are attracted to the cathode. They gain electrons (a process called reduction) and are transformed into neutral sodium metal.1
At the Anode (Positive Electrode): Negatively charged chloride ions ( $C l^{-}$ ) are attracted to the anode. They give up their electrons (a process called oxidation) and are transformed into neutral chlorine gas.1

This method, notably utilized in the Downs cell process, allows for the large-scale industrial production of both sodium metal and chlorine gas.2