Question

What is the approximate strength of current that will deposit 0.5 gm of silver on a spoon in 7.5 minutes?
(A) 1 A
(B) 0.005 A
(C) 0.1 A
(D) 0.5 A

Answer 1

Hint: Michael Faraday did considerable research on electrolysis of electrolyte solutions and melts. He was the first scientist to define the Laws of Electrolysis in quantitative terms. He suggested two laws to describe the quantitative features of electrolysis, which are today known as Faraday's laws of electrolysis, namely the first and second laws of electrolysis. We use this concept here.
 $ M{\text{ }} = {\text{ }}Z{\text{ }}I{\text{ }}t $
M is mass
Z is constant of proportionality
I is current in amperes
t is time.

Complete answer:
One of the fundamental rules of electrolysis is Faraday's - First Law of Electrolysis. It says that the amount of chemical reaction that takes place at any electrode under the influence of electrical energy is proportionate to the amount of electricity that passes through the electrolyte during electrolysis.
Second Law of Electrolysis by Faraday states that when the same amount of power is passed through the electrolytic solution, a variety of compounds are released in proportion to their chemical equivalent weights (Equivalent weight is defined as the ratio of the atomic mass of metal and the number of electrons required for reducing the cation).
Now given
Given: $ W = 0.5{\text{ }}gm $
  $ t = 7.5{\text{ }}minutes{\text{ }} = 450{\text{ }}\sec $
Electrochemical equivalent of Ag is given as
 $ Z = \dfrac{{108}}{{96500}}\quad {\text{gm }}{C^{ - 1}} $
Using $ W{\text{ }} = {\text{ }}Z{\text{ }}I{\text{ }}t $
Substituting the values
 $ \therefore 0.5 = \dfrac{{108}}{{96500}} \times {\text{I}} \times 450 $
Hence
 $ \Rightarrow {\text{I}} \approx 1\;{\text{A}} $ .

Note:
We need to know about the electrochemical equivalents of various elements thoroughly. Electrolysis is a chemistry and industrial technology that employs direct electric current (DC) to drive a chemical reaction that would otherwise be non-spontaneous. Electrolysis is crucial in the industrial separation of elements from naturally occurring sources like ores using an electrolytic cell. The decomposition potential is the voltage required for electrolysis to occur.