Electrolysis of Potassium Chloride.
Potassium chloride
must be heated until it is molten
before it
will conduct electricity.
Electrolysis separates the
molten ionic compound into its
elements.
The reactions at each electrode are called half
equations.
The half equations are written so that
the same number of electrons
occur in each equation.
2K+ + 2e- 
2K (potassium
metal at the (-)cathode).
2Cl- -
2e-
Cl2
(chlorine gas at the (+)anode).
Potassium ions
gain
electrons (reduction) to form
potassium atoms.
Chloride ions lose
electrons (oxidation) to form
chlorine atoms.
The chlorine atoms combine to form molecules of
chlorine gas.
The overall reaction is
2K+Cl-(l)
2K(s) + Cl2(g)
See some other examples of electrolysis.
Links Electrolysis
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