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Homework Help: Determination of Faraday's

  1. Apr 19, 2006 #1
    using the number obtained 3.407x10^-8 coulombs/mole and the fact that one electron has a charge of 1.60x10^-19 coulombs, calculate how many electrons there are in one mole (i.e. Avogadro's number)


    I am not sure but do you do this problem like this?

    3.407x10^-8coulombs/mole x 6.022x10^23electrons/mole divide 1.60x10^-19coulombs
     
  2. jcsd
  3. Apr 19, 2006 #2

    Hootenanny

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    Yep, that looks good to me.

    ~H
     
  4. Apr 19, 2006 #3

    Gokul43201

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    Please state the entire question - not just a part of it. Where was the number 3.407... obtained from ?

    That doesn't look right to me (for one thing, it has units of [mole^-2] which are meaningless), but neither does the question as posted.
     
  5. Apr 19, 2006 #4

    dav2008

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    The huge problem here is that you (improperly) used the number of electrons in a mole to determine...the number of electrons in a mole.

    The problem basically boils down to "how many electrons does it take to give a charge of 3.407e-8 C.

    Again as it was said above, the first given number is a bit suspicious...
     
    Last edited: Apr 19, 2006
  6. Apr 19, 2006 #5
    In Lab I did an experiment in class on trying to determine Faraday's constant and I got 3.407x10^-8 and I have to used that on my calculations
     
  7. Apr 19, 2006 #6

    dav2008

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    Well I hate to break your hopes but you're off by a factor of 1012.

    But yes like I said you just want to determine how many electrons it would take to get the charge that you experimentally determined. It's just a simple factor label problem. You are given C/m (Coulombs per mole) and want to determine N/m (number of electrons per mole) given C/N (Charge per electron)
     
    Last edited: Apr 19, 2006
  8. Apr 20, 2006 #7
    oh so its 3.407x10^-8 C/m divide 1.60x10^-19coulombs which equals to

    2.12938E^11 N/m (number of electrons per mole)
     
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