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About Faraday constant

  1. Jun 17, 2014 #1
    The faraday constant is prayed:
    $$\\ 1\; \text{F} = \frac{96 500\;\text{C}}{1\;\text{mol}}$$

    I'm wrong if I say that the faraday constant is:
    $$\\ 1\; \text{F} = \frac{96 500\;\text{C}}{1\;\text{mol e}}$$
  2. jcsd
  3. Jun 17, 2014 #2


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    You are right, mole and mol is the same.
  4. Jun 17, 2014 #3
    I'm not talking about mol and mole, I'm talking about mol and mol of electron!
  5. Jun 17, 2014 #4


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    Then that is incorrect then. It is a constant and the units are specifically defined. The fact that it is representative of the charge of a mole of electrons does not change its units to reflect that it is of electrons or the fact that it is just a number.
  6. Jun 17, 2014 #5
    Hummm, but 1 mol e ≠ 1 mol p, so the electrical charge associated to 1 mol of eletrons is very different to charge associated to 1 mol of protons.

    looks this article: http://en.wikipedia.org/wiki/Stoichiometry#Determining_amount_of_product

    Make very much sense say x mol A, y mol B and z mol C than simply say x mol, y mol or z mol.

    Until today I don't understand why what is being counted is omited of front of mol...
  7. Jun 17, 2014 #6


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    The Faraday constant for a mole of electrons is the same as a mole of protons since it does not carry a sign as far as I can see. The Faraday constant could be talking about mole of sodium ions or many other things. We do not include such things in the units. It is just a bookkeeping factor you have to carry forward on your own. It is done all the time in physics. Coulomb's Law is for unit charges but we easily apply a constant prefactor to adjust it for bodies with multiple electrons worth of charge. Yet we do not show this in the units we choose for e the equation.
  8. Jun 17, 2014 #7
    Saying mol A, mol B, etc.. is like saying the dimensions of an object are 3 meters high, 2 meters wide and 5 meters long. high, wide and long are added to describe what is being measured but they are not part of the unit.
  9. Jun 17, 2014 #8
    *I think* that when about particles, not should be omited, IMO. Cause you have an infinity of particles, elements and molecules all with different properties...
  10. Jun 17, 2014 #9
    You are missing the whole point of introducing this constant.

    What Faraday has observed is that the SAME amount of charge (or multiples of it) is necessary to go through the solution in order to separate or deposit one mole of ANY substance.
    This "ANY" is reflected in the unit of C/mole. Any mole.

    The same charge is carried by a mole of either electrons, protons, sodium ions, chlorine ions, etc.
    Or twice as much charge is carried by one mole of calcium ions, copper II ions, etc.
  11. Jun 17, 2014 #10

    D H

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    Or even a mole of moles, with each mole being stripped of exactly one electron.
  12. Jun 18, 2014 #11
    I don't believe!
  13. Jun 18, 2014 #12
    OK. No problem. :smile:
  14. Jun 18, 2014 #13


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