Electrolysis Calculator
Faraday's law: mass deposited from charge passed.
Work out Electrolysis. Faraday's law: mass deposited from charge passed. Says where the approximation breaks.
2 for Cu²⁺, 1 for Ag⁺, 3 for Al³⁺.
Mass deposited (g)
2.37099
7,200 C · 0.037311 mol
Faraday's law: charge divided by 96,485 C gives moles of electrons, then divide by the ionic charge for moles of substance. That constant is exact since 2019, being Avogadro's number times the elementary charge. The electrons-per-ion figure is what people miss — depositing a mole of copper(II) takes two moles of electrons, so at the same current it takes twice as long as a mole of silver.
How the Electrolysis Calculator works
Charge divided by 96,485 C gives moles of electrons, then divide by the ionic charge for moles of substance. That constant is exact since 2019, being Avogadro's number times the elementary charge.
Also known as: faradays law calculator · electroplating calculator · mass deposited calculator · faraday's law of electrolysis
Frequently asked questions
What is Faraday's law of electrolysis?
The mass deposited is proportional to the charge passed. One faraday, 96,485 coulombs, deposits one mole of a singly-charged ion.
Why does copper take twice as long as silver?
Because Cu²⁺ needs two electrons per atom and Ag⁺ needs one. At the same current, depositing a mole of copper takes twice the charge.
How do I work out plating time?
Convert the target mass to moles, multiply by the electrons per ion and by the Faraday constant to get the charge, then divide by the current.
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