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Homework Help: Spin of hydrogen atom

  1. Sep 12, 2008 #1
    if the electron has spin 1/2 and proton has spin 1/2, why is the hydrogen atom (which is made of the electron and proton) have spin of 1/2?
     
  2. jcsd
  3. Sep 12, 2008 #2

    Redbelly98

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    It doesn't. Hydrogen can have a spin of either 0 or 1.

    Assuming we mean the isotope whose nucleus has one proton and no neutrons.
     
  4. Sep 12, 2008 #3
  5. Sep 12, 2008 #4

    Redbelly98

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    Weird. I noticed it says Spin 1/2+. I don't know what the + is supposed to mean.
     
  6. Sep 12, 2008 #5

    alphysicist

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    I believe that the 1/2+ is the nuclear spin and parity.
     
  7. Sep 13, 2008 #6
    can you add electron and nuclear spin? I thought they were completely different.
     
  8. Sep 13, 2008 #7

    Ygggdrasil

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    When we talk about the spin of hydrogen, we are talking about the spin of the hydrogen nucleus (i.e. a proton). The electron doesn't figure into this.
     
  9. Sep 13, 2008 #8

    Redbelly98

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    Thanks for clarifying everybody.

    FYI, when laser cooling is used to make Bose-Einstein condensates with atoms, the electron and nuclear spins both figure into determining whether the atom is a boson or fermion.
     
  10. Sep 14, 2008 #9
    you mean the other way around? electron spin matters since it's intrinsic magnetic moment is much greater than the hydrogen nucleus. this is because the proton mass >> electron mass
     
  11. Sep 14, 2008 #10

    Ygggdrasil

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    Most of the time I've heard people discuss the spin of hydrogen is in the context of NMR spectroscopy, a technique that measures the energy differences between nuclear spin states in the presence of a magnetic field. For this technique, the spin of the electrons are not important.
     
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