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B Do galvanic cells depend on distance?

  1. Aug 13, 2016 #1
    I have seen some sites say that it doesn't and other says the opposite. So lets see
    h2vcudiag.gif
    Source of the pic: Chemguide

    Lets look at the hydrogen (Oxidation) half cell. If we assume that it contributes x volts until the electron reachs the copper, then no matter how big is the distance the voltage is going to be the same ( only the Electric field will be weak and the current will decrease)

    However if we look at both cells together and try to move the copper away from the hydrogen and look at the contribution of the copper electrode, First opposing the current, by exerting a force in the other direction. So when you move it away, you are making the potential of the electrons in the platinum decrease.
    So if we assume that the voltage at the copper electrode ( without the contribution of hydrogen) is y and the voltage at the hydrogen is z at the initial state then you move it away z will decrease so the difference will increase thus opposing the current more


    Is this a explanation true?
     
  2. jcsd
  3. Aug 14, 2016 #2
    Any answer?
     
  4. Aug 14, 2016 #3

    NascentOxygen

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    Staff: Mentor

    These are electrodes immersed in liquid electrolyte, and you're envisioning a tiny electrostatic repulsion between the plates due to the charges on each? I don't think that comes into the picture, but we'll see if someone can set you right.
     
  5. Aug 14, 2016 #4

    Nvm, Anyone who is reading this thread. I already figured it out

    Thanks NascentOxygen
     
    Last edited: Aug 14, 2016
  6. Aug 14, 2016 #5

    NascentOxygen

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    Staff: Mentor

    Even if you make the surface area of each electrode 100 times greater, a galvanic cell's voltage doesn't change.
     
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