Faraday Electrolysis Law

\[m=\frac{ItM}{nF}\]

Variables

mmass deposited or liberated (g)

Ielectric current (A)

telectrolysis time (s)

Mmolar mass of substance (g/mol)

nnumber of electrons transferred

FFaraday constant (96485 C/mol)

Description

What is this formula?

Faraday's Law of Electrolysis calculates the amount of substance produced or consumed during an electrochemical process based on the electric charge passed through the system.

It directly links electricity and chemical transformation.

When to use it

Use this formula when calculating metal deposition, electroplating thickness, electrorefining production, gas generation, or electrolysis yields.

Example

Given:

I = 5.0 A

t = 3600 s

M = 63.55 g/mol (Cu)

n = 2

F = 96485 C/mol

Formula:

m = (ItM)/(nF)

Substitution:

m = (5×3600×63.55)/(2×96485)

Result:

m ≈ 5.93 g

Approximately 5.93 grams of copper are deposited.

Applications

Electroplating

Electrorefining

Battery technology

Industrial electrolysis

Corrosion studies

Chemical engineering

Note

Faraday's Law assumes 100% current efficiency, meaning that all electrical charge contributes to the desired electrochemical reaction.

In industrial systems, side reactions, gas evolution, impurities, and transport limitations may reduce the actual yield.

The total electric charge is:

Q = I × t

and one Faraday (96485 C) corresponds to one mole of electrons transferred.