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Homework Help: Atomic energy levels

  1. Mar 26, 2009 #1
    1. The problem statement, all variables and given/known data

    Calculate the five (5) lowest energy levels for the hydrogen atom using Bohr's model.

    2. Relevant equations

    [tex]E_{n}= -2\xime^4 Z^2/h^2 n^2[\tex]

    = [tex]-(2.178\times10^18 J)Z^2/n^2[\tex]

    3. The attempt at a solution

    I get how to attempt it but how can there be 5 lowest energy levels when hydrogen has only one energy level. I'm puzzled.
  2. jcsd
  3. Mar 26, 2009 #2


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    Hydrogen has infinitely many energy levels, corresponding to n=1,2,3,etc.

    Why did you think there is only one level?
  4. Mar 26, 2009 #3
    Electron arrangement of hydrogen and drawing it out basicly only shows one ring.
    Thinks that this is the only energy level.
    Thats my guess, I got confused about that when I first started the topic.

    P.S. Eventually has an ionisation level does it not? so not infinite energy levels.
  5. Mar 26, 2009 #4


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    Typically, you will see diagrams showing an atom in it's lowest-energy state. I am guessing this is the figure you have seen. However, there are in fact more energy levels -- infinitely many -- between this lowest energy and the ionization level.

    Normally an atom will be in the lowest-energy state most of the time. But it is possible to excite the atom into the higher states (without ionizing it), for example by shining light of the appropriate wavelength at the atom.

    EDIT: adding links
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