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Which electron travels from - to +?

  1. Mar 26, 2008 #1
    Ok, let me try to state this properly (I don't know much about this, so try to understand what I am trying to say rather than pick apart any error).


    NI - Negative Ion
    A - Atom
    PI -Positive Ion

    Now, one electron from NI travels towards PI as in a circuit. Is the electron that left NI the same as the one that reaches PI? Or do the A's just send the one that happens to be closest to PI when they become negatively charged?

    One other question while I am at it: Is there any significance to + being assigned to protons and - being assigned to electrons or is this arbitrary? Stated differently, is there any theory or phenomenon that would "break" if you where to switch and say that the proton is negative and the electron is positive?

    Help a noobie out.

  2. jcsd
  3. Mar 26, 2008 #2
    As for your first question, I would guess that it would depend on how the ions/atoms are bonded as to whether or not it is the original electron that travels to the PI. For instance, if the atoms in between NI and PI are conductive, they will have a conduction band of valence electrons that freely move, so I would argue that it is probably not the original electron that moves to the PI, however, if say your atoms in between are insulators, that may not be the case, it might be that the electrons will not move at all.

    For your other question. The + and - assigned to protons and electrons respectively is completely arbitrary (as I recall it was Ben Franklin that first assigned the + and -). As magnetostatics, and other E&M theories were created, the consensus was that the positive charges are moving in wires, however, we know that it is in fact that the negative charges move. So, it would make sense to either change that theory to negative charges moving, or to call protons negative and electrons positive. In actuality, no theories or phenomenon will "break" but they would potentially make more sense.
  4. Mar 27, 2008 #3
    Aye, that was what I was getting at. Everything would be much more straight forward mathematicly if we assigned the positive charge to the electron.


    H(3+) - e = H(2+)

    Rather than

    H(3+) - e = H(4+)

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