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Energy levels in atoms

  1. Apr 9, 2013 #1
    Why do electrons closer to nucleus have
    Less energy than electrons first away?

  2. jcsd
  3. Apr 9, 2013 #2
    I guess the other way is true: The electrons that are closer to nucleus require more energy to remove from the atom. The outer electrons can be removed with less energy when compared to electrons that are closer to nucleus. Hope it helps.
  4. Apr 9, 2013 #3

    Simon Bridge

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    They have a lower energy level because they are held tighter ... thought about another way: the electrons must be moving faster (higher kinetic energy) in order to avoid being pulled closer.
  5. Apr 9, 2013 #4


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    Staff: Mentor

    True! However, when the electron is "completely removed" we say (by convention) that it has zero energy. Electrons that are bound in an atom have negative energy. When removing an electron, we add energy, raising it from negative to zero. If an electron requires more energy to remove, it must have been at a lower (more negative) energy to begin with.

    Think of raising an object out of a hole in the ground.
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