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Faraday constant

In physics and chemistry, the Faraday constant is the amount of electric charge of one mole of electrons.

It has the symbol F, and is given by

where NA is Avogadro's number (approximately 6.02 x 1023) and q is the charge on an electron.

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. This value was used to calculate Avogadro's number. Research is continuing into more accurate ways of determining F, and thereby NA. There are plans to use this value to redefine the kilogram in terms of a known number of atoms. [Source: NPL Annual Review 1999]

F = 964 85.309 29 C/mol 0.028 945 6 C/mol [Horner's Physics Constants, 1999]

F = 96 485.3415 C/mol 0.0039 C/mol [NIST, 2003, quoting CODATA, 1998]

The Faraday constant was named after British scientist Michael Faraday.