In physics and chemistry, the Faraday constant (named after Michael Faraday) is the magnitude of electric charge per mole of electrons.^[1] The Faraday constant, denoted F, is widely used in calculations in electrochemistry, and has the currently accepted value:^[2]

F = 96 485.3399(24) C/mol

The constant F has a simple relation to two other physical constants:

F = Ne

where N_A is the Avogadro constant (approximately 6.02 mol^?1) and e is the elementary charge, the magnitude of the charge on an electron (approximately 1.602 C). This relation is true because the amount of charge of a mole of electrons is equal to the amount of charge in one electron, multiplied by the number of electrons in a mole.

The value of F was first determined by weighing the amount of silver deposited in an electrochemical reaction in which a measured current was passed for a measured time, and using Faraday's law of electrolysis.^[3] Research is continuing into more accurate ways of determining the interrelated constants F, N_A, and e.

See also

• Michael Faraday
• Faraday's law of Electromagnetic induction
• Faraday's law of electrolysis

References

1. ↑ The term "magnitude" is used in the sense of "absolute value": The charge of an electron is negative, but F is always defined to be positive.
2. ↑ CODATA 2006
3. ↑ NIST Introduction to physical constants