Faraday constant

(noun)

The magnitude of electric charge per mole of electrons.

Related Terms

Examples of Faraday constant in the following topics:

  • Thermodynamics of Redox Reactions

    • If T is held constant at 298K, the Nernst equation can be condensed using the values for the constants R and F:
    • It can be further simplified if the reaction has reached equilibrium, as in that case Q is the equilibrium constant K:
    • This equation allows the equilibrium constant to be calculated just from the standard reduction potential and the number of electrons transferred in the reaction.
    • Translate between the equilibrium constant/reaction quotient, the standard reduction potential, and the Gibbs free energy change for a given redox reaction

  • Resting Membrane Potentials

    • R is the universal gas constant, equal to 8.314 joules·K−1·mol−1.
    • F is the Faraday constant, equal to 96,485 coulombs·mol−1 or J·V−1·mol−1 .
    • Goldman equation: R is the universal gas constant, equal to 8.314 joules·K−1·mol−1 T is the absolute temperature, measured in kelvins (= K = degrees Celsius + 273.15) F is the Faraday constant, equal to 96,485 coulombs·mol−1 or J·V−1·mol−1

  • Concentration of Cells

    • Here, ΔG is the change in Gibbs free energy, T is absolute temperature, R is the gas constant, and Q is the reaction quotient.
    • Here, n is the number of moles of electrons, F is the Faraday constant ($\frac {Coulombs}{mole}$), and ΔE is the cell potential.

  • Avogador's Number

    • The actual number of atoms or molecules in one mole is called Avogadro's constant (NA), in recognition of Italian scientist Amedeo Avogadro .
    • The value of Avogadro's constant, NA , has been found to equal 6.02×1023 mol−1.
    • Avogadro's constant is a scaling factor between macroscopic and microscopic (atomic scale) observations of nature.
    • As such, it provides the relation between other physical constants and properties.
    • For example, it establishes a relationship between the gas constant R and the Boltzmann constant k,

  • Free Energy and Cell Potential

    • Here, n is the number of moles of electrons and F is the Faraday constant (96,485$\frac {Coulombs}{mole}$).

  • Electrostatic Shielding

    • Electrostatic shielding is the phenomenon that occurs when a Faraday cage blocks the effects of an electric field.
    • A Faraday cage is a closed chamber consisting of a conducting material or a mesh of such a material.
    • The action of a Faraday cage may depend on whether or not it is grounded.
    • Electrical linemen often wear suits made of Faraday cages so as to avoid electrocution.
    • Elevators can act as unintended Faraday cages, shielding cell phones and radios from signal from the outside.

  • Induced EMF and Magnetic Flux

    • The apparatus used by Faraday to demonstrate that magnetic fields can create currents is illustrated in the following figure.
    • For a varying magnetic field, we first consider the magnetic flux $d\Phi _B$ through an infinitesimal area element dA, where we may consider the field to be constant:

  • Maxwell's Predictions and Hertz' Confirmation

    • Combining the work of physicists including Oersted, Coulomb, Gauss, and Faraday, and adding his own insights, James Clerk Maxwell developed a complete and overarching theory showing electric and magnetic forces are not separate, but different forms of the same thing: the electromagnetic force.
    • The strength of the force is related to the electric constant ε0, also known as the permitivity of free space.

  • Electrolysis Stoichiometry

    • It takes 96,485 coulombs to constitute a mole of electrons, a unit known as the faraday (F).
    • This relation was first formulated by Michael Faraday in 1832, in the form of two laws of electrolysis:
    • Thus, one mole of V3+ corresponds to three equivalents of this species, and will require three faradays of charge to deposit it as metallic vanadium ($V^{3+} + 3e^- \rightarrow V$).

  • The Inventions of the Telephone and Electricity

    • Thomas Edison's major innovation was the first industrial research lab, which was built in Menlo Park, New Jersey and was the first institution set up for the specific purpose of producing constant technological innovation.
    • In the years of 1831–1832, Michael Faraday discovered the operating principle of electromagnetic generators.