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Extraction of Metals

Electrolysis of Magnesium Chloride.

Magnesium chloride must be heated until it is molten
before it will conduct electricity. Electrolysis
separates the molten ionic compound into its elements.

Electrolysis of Magnesium Chloride

The half equations are

Mg2+  +  2e-    arrow   Mg (magnesium metal at the (-)cathode).
Cl-  -  2e-    arrow   Cl2 (chlorine gas at the (+)anode).

Magnesium ions gain electrons (reduction) to form magnesium atoms.
Chloride ions lose electrons (oxidation) to form chlorine atoms.
The chlorine atoms combine to form molecules of chlorine gas.

The overall reaction is

MgCl2(l)      arrow     Mg(s)  +   Cl2(g)

See some other examples of electrolysis.

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