gcsescience.com 6 gcsescience.com
Extraction of Metals
Electrolysis of 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
The half equations are written so that the same number of electrons
occur in each equation.
2K+ + 2e-
metal at the (-)cathode).
2Cl- - 2e- Cl2 (chlorine gas at the (+)anode).
electrons (reduction) to form
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 Revision Questions
gcsescience.com The Periodic Table Index Metal Quiz gcsescience.com
Home GCSE Chemistry GCSE Physics
Copyright © 2015 gcsescience.com. All Rights Reserved.