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Are atoms electrically neutral?

  1. Sep 25, 2006 #1
    What is the difference between an atom and an ion? Ion has net electric charge. So it shows electric property. It acts like a small charged ball. What about an atom? Does it behave as a neutral object?
    Atom has equal number of protons and electrons bind together in the space. For this it is said to be electrically neutral. But electricity is a vector quantity, so equal number of positive and negetive charges doesn't essentially cancel out the effect of each other.
    Let's take hydrogen atom for example. It has an electron that is orbiting around a proton. At any instance of time, there is a point between this two charged particle that is neutral (according to couloumb's law). But as a whole this system will have net electric property. So a hydrogen atom should behave like a charged object rather than being neutral.
    Actually the nature of electric force (static) is such that charges distributed in space (like or unlike), always creates an electric field.
    So atoms are not electrically neutral at all!
    Am I right? Please confirm me.
  2. jcsd
  3. Sep 25, 2006 #2
    Gross, they are electrically neutral - obviously, because they have the same number of positive and negative charges.

    Your analysis is flawed because electrons don't behave as little points whizzing around the nucleus.

    However, a similar effect can still exist. Expose a proton-electron system of any kind to an electric field, and the proton and electron will shift relative to one another in response, creating their own electric field. This is called polarisation.

    (Electric polarisation that is; optical polarisation is something entirely different).

    None of this alters the fact that overall, atoms are electrically neutral - though the statement itself is highly simplified and one might say logically insufficient.
  4. Sep 25, 2006 #3


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    "electricity" is not a vector quantity! The electric field, at any point is a vector but you are talking about charge which definitely is a scalar (numeric) quantity.
  5. Sep 25, 2006 #4
    At any instance of time, there is a point between this two charged particle that is neutral (according to couloumb's law).

    There is no such point in a dipole
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