Electrolysis Calculator
Relate electrical charge, electrons transferred, and molar mass to predict the amount of material produced at an electrode.
For Cu2+ to Cu use n = 2, for Al3+ use n = 3, and so on.
Use 100 for ideal conversion. Lower values account for side reactions.
Charge passed
9,000 C
Substance (mol)
0.0443 mol
Substance (g)
2.8155 g
How to Use This Calculator
Measure current and duration
Record the steady current applied and the electrolysis time interval.
Specify substance properties
Enter molar mass and the number of electrons required per mole of product.
Estimate efficiency
Adjust for side reactions or incomplete collection using a percent efficiency.
Review predicted yield
The calculator returns charge, moles, and mass deposited or evolved.
Formula
m = (I t M η) / (n F)
Charge equals I t. Moles equal charge times efficiency divided by nF. Mass equals moles times molar mass M. Use F = 96485 C/mol.
Example
Passing 5 A for 1800 s with Cu2+ (n = 2) at 95 percent efficiency deposits m = 5 * 1800 * 63.546 * 0.95 / (2 * 96485) ≈ 2.8 g of copper.
Full Description
Faraday's laws connect electrical charge with chemical change at electrodes. Knowing the current, duration, and electron stoichiometry lets you predict yields without running the experiment.
This tool streamlines plating, gas evolution, and synthesis planning by reporting both theoretical and efficiency-adjusted outputs.
Frequently Asked Questions
Can I use minutes instead of seconds?
Convert minutes or hours to seconds before entering the time value to keep units consistent.
What if current is not constant?
Use the average current over the interval or integrate the current profile to find total charge.
How do I pick efficiency?
Start with literature or equipment guidance. You can adjust the percentage after comparing with experimental results.
Does solution concentration matter?
Faraday's law tracks charge balance. Mass transport limits or depletion may reduce actual yield, reflected in the efficiency factor.
Can this handle gas evolution?
Yes. Use the molar mass of the gas to convert moles to grams, or use moles directly for volume estimates via the ideal gas law.