Industrial Electrolytic Processes
Aluminium is obtained by the electrolytic reduction of its molten oxide,
alumina (Al2O3). Because alumina has a very high melting point (2045 C),
the mineral cryolite (Na3AlF6) is added to lower the melting point in order
that the electrolysis may be carried out at about 950 C. The electrolytic
cell has carbon anodes and a carbon cathode (which forms the lining of the
tank in which the electrolysis takes place). Carbon dioxide is formed at
the anodes, and aluminium at the cathode. It is heavier than the molten
alumina/cryolite mixture, and sinks to the bottom of the cell, where it is
tapped off. The procedure is known as the Hall-Heroult process.
Aluminium extraction is very demanding on electrical current (typically,
800 V and 70 000 A), and is economical only where power is cheap.
Silver Plated Cutlery
Electroplating consists of depositing a thin layer of a metal on another,
either for protection or for the sake of appearance. Typically, a brass or
nickel object is coated with a layer of silver by making use of
electrolysis of a silver solution, using the object to be coated as the
The anode consists of pure silver, and the cathode is the object to be
plated. The electrolyte is a mixture of silver nitrate with potassium
The reactions are:
At the anode: Ag picAg+ + e-
At the cathode: Ag+ + e- picAg
The cyanide ensures a low concentration of silver ions, a condition for
providing the best plating
Electrolysis has improved the quality of life in western society. Without
Electrolysis many things that we as a society take for granted would not
exists. The simplest thing as a phone would not work without copper wiring.
Computers’ cars and most other forms of modern technology would not exist
without the basic materials that are obtained from electrolysis.
1. Transportation is a fast growing necessity for the modern country and
its growing metropolises. Without it a country would not be able to
continue living profitably. My education would be inaccessible
2. Communication is essential in this day and age and is taken for
granted I would be unable to communicate with friend and family who
live great distances away from me.
3. Technology such as computers would limit my information and my ability
to school assignments and substantially reduce my out put.