Faraday's First Law of Electrolysis:
Statement:
Faraday's first law of electrolysis states that the amount of a substance deposited or liberated at an electrode during electrolysis is directly proportional to the amount of electric charge passed through the electrolyte.
Mathematical Form:
The law can be expressed as:
\(m = \frac{M \cdot Q}{F \cdot z}\)
where: - \(m\) is the mass of the substance deposited or liberated, - \(M\) is the molar mass of the substance, - \(Q\) is the total charge passed through the electrolyte (in coulombs), - \(F\) is the Faraday constant (approximately 96500 C/mol), - \(z\) is the valency of the ion (the number of electrons involved in the reaction).Implication:
This law indicates that the amount of substance deposited or liberated at the electrodes is proportional to the total charge passed, making electrolysis a controlled method for determining the quantity of material involved in redox reactions. Faraday’s first law is fundamental to understanding electroplating, electrorefining, and the electrolysis of water and salts.
Standard electrode potential for \( \text{Sn}^{4+}/\text{Sn}^{2+} \) couple is +0.15 V and that for the \( \text{Cr}^{3+}/\text{Cr} \) couple is -0.74 V. The two couples in their standard states are connected to make a cell. The cell potential will be:
To calculate the cell potential (\( E^\circ_{\text{cell}} \)), we use the standard electrode potentials of the given redox couples.
Given data:
\( E^\circ_{\text{Sn}^{4+}/\text{Sn}^{2+}} = +0.15V \)
\( E^\circ_{\text{Cr}^{3+}/\text{Cr}} = -0.74V \)
