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Low temp physics

  1. Feb 24, 2013 #1
    1. The problem statement, all variables and given/known data
    Why at absolute zero does He (three) have a larger molar volume and require a higher pressure to solidify than He(four)?

    3. The attempt at a solution

    I feel the answer lies in the Pauli exclusion principle, at low temps the ferions are nopt as easily confined as the bosons so they will have a larger molar volume, but i can't explain why this would then require a higher pressure to solidify:

    Pv = nRT

    where if v is increased surely P must decrease?
  2. jcsd
  3. Feb 24, 2013 #2


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    2017 Award

    Staff: Mentor

    I think I saw some pairing process for He3 - so you have to consider "molecules" (those are bosons again) instead of atoms.
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