Question

The amt. of an ion liberated on an electrode during electrolysis does not depend on the

• A. Conductance of the solution
• B. Current strength
• C. Time
• D. Electrochemical equivalent of the element

Answer 1

Answer: (A)

Conductance of the solution

Answer 2

Faraday's first law of electrolysis states that the mass of a substance ($w$) deposited or liberated at any electrode is directly proportional to the quantity of electricity ($Q$) passed through the electrolyte.

$w \propto Q$

The quantity of electricity ($Q$) is the product of current strength ($I$) and time ($t$).

$Q = I \times t$

Combining these, we get $w \propto I \times t$.

Faraday's second law of electrolysis leads to the introduction of the electrochemical equivalent ($z$). The mass of a substance deposited or liberated is given by:

$w = z \times Q = z \times I \times t$

This equation shows that the amount of substance liberated ($w$) depends on:

1. The electrochemical equivalent of the element ($z$)
2. The current strength ($I$)
3. The time ($t$)

Conductance ($G$) is a measure of how easily electric current flows through the solution. It is related to resistance ($R$) by $G = 1/R$. While conductance affects the current that flows for a given voltage ($I = VG$), the amount liberated is determined by the actual current ($I$) that passes, as shown in the formula $w = zIt$. The formula does not directly involve conductance. If the current and time are known, the conductance of the solution does not affect the amount liberated.