Electrolytic deposition and quantity of electricity (Faraday's first law)

Principle

During an electrolysis reaction, the deposited mass m of a substance is directly proportional to the flow of charge (First Faraday's law). The second Faraday law states that the electrochemical equivalents k (deposited mass per charge unit) behave like the equivalent masses (molar mass M divided by the valency z) of the elements. Both laws can be confirmed experimentally by water decomposition using an apparatus according to Hofmann.

Learning objectives

• Faraday law
• Water decomposion by electrolysis
• Calculation of deposited mass during an electrolysis