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(iii) Electrochemistry:
Basic Principles of Electrochemistry
Basic Principles of Electrolysis
Electrolysis refers to the process in which a compound, typically an ionic substance, is decomposed by
passing an electric current through it. The substance being decomposed can be either molten or in aqueous
solution.
Electrolyte: The molten or aqueous ionic compound that undergoes electrolysis. It conducts electricity due
to the presence of free-moving ions.
Electrodes: Conductors through which the electric current enters and leaves the electrolyte.
Anode (Positive Electrode): Electrons are lost here (oxidation occurs).
Cathode (Negative Electrode): Electrons are gained here (reduction occurs).
Inert Electrodes: Electrodes that do not react with the electrolyte. Graphite or platinum are commonly used.
Charge Transfer in Electrolysis:
At the Cathode (Negative Electrode):
Cations (positive ions) move towards the cathode and gain electrons, undergoing reduction.
The products may be metal deposition or hydrogen gas, depending on the reactivity of the ions.
At the Anode (Positive Electrode):
Anions (negative ions) move towards the anode and lose electrons, undergoing oxidation.
The products are typically non-metallic elements or oxygen gas.