Question

According to Faraday’s law of electrolysis, the amount of decomposition is proportional to:
A. $ \frac{1}{Time~for~which~current~passes}$
B. Electrochemical equivalent of the substance
C. $\frac{1}{current}$
D. $\frac{1}{Electrochemical~equivalent}$

Answer 1

Hint: The proportionality constant in the mathematical expression given by Faraday’s law of electrolysis will determine the amount of deposition. Be familiar with the terms in the equation. It will help in answering the given problem.

Complete Step by Step Answer:
The amount of reaction occurring in terms of the mass of ions created or released from an electrolyte is proportionate to the amount of electric current carried, according to Faraday's first electrolysis law. Since the amount of coulombs (Q) flowing in a second equals the amount of electric current (ampere),
$m\varpropto~Q$
$m\varpropto~ZQ$
Also,
$m=Zit$ (Current is defined as the charge per unit time)
Where Z is the proportionality constant termed as the chemical equivalent of an element.
$m=Z$, for a flow of one Coulomb of charges over a second.
The mass of the substance used in the reaction is the same as the proportionality constant. One coulomb charge's electrochemical equivalent mass is Z.
Therefore, the mass of the material released during electrolysis, or the amount of breakdown, is proportional to the substance's electrochemical equivalent.
Using the formula $m=Zit$ where I is current, t is time, and m is the mass deposited or freed, Z is its electrochemical equivalent.
It is possible to state that the mass deposited will correspond to the substance's electrochemical equivalent.
The correct option is B.

Note: According to Faraday's Law, $m=ZQ$ or $m=Zit$. One equivalent (or mole) of electrons flowing per second will amount to 96485 Equivalent mass when one coulomb is equal to one electrochemical equivalent mass (Z) of the substance.