Faraday’ s Laws of Electrolysis
Faraday’ s Laws of Electrolysis
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Michael Faraday described the quantitative aspects of electrolysis and came forward with two laws of electrolysis:
1 st Law: The amount of chemical reaction which occurs at any electrode during electrolysis by a current is proportional to the quantity of electricity passed through the electrolyte( solution or melt).
2 nd Law: The amounts of different substances liberated by the same quantity of electricity passing through the electrolytic solution are proportional to their chemical equivalent weights
Mathematically, Atomic Mass of Metal ÷ Number of electrons required to reduce the cation.
Q = It where Q is in coloumb
I is in ampere and t is in second.
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This quantity of electricity is known as Faraday and is represented by the symbol F. o In the above example application of more current results in the deposition of more amount of copper from the anode to the cathode.
PROBLEM:
IF A CURRENT OF 0.5 AMPERE FLOWS THROUGH A METALLIC WIRE FOR 2 HOURS, THEN HOW MANY ELECTRONS WOULD FLOW THROUGH THE WIRE?
Solution: I = 0.5 A t = 2 hours = 7200 s By using the formula, Q = It = 0.5 A × 7200 s