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Homework Help: Molecular Weight and BP, MP

  1. Dec 7, 2009 #1
    While both molecules have a very similar molecular weight, their boiling and melting points vary significantly. Explain the behavoir.

    i have look everywhere to try and figure out why the bp and mp are different from mw but i just can't get anywhere!
  2. jcsd
  3. Dec 7, 2009 #2
    what kinds of compounds are you talking about?
  4. Dec 7, 2009 #3
    ethane and formaldehyde
  5. Dec 7, 2009 #4
    what's the structure of formaldehyde? I forgot.
  6. Dec 7, 2009 #5
    does this have to do with intermolecular interactions?
  7. Dec 7, 2009 #6
    if it does, it's because stronger intermolecular forces occur between the different components of formaldehyde like hydrogen bonding, dipole-dipole interactions, and London forces while only London forces occur in between the different components of ethane, giving formaldehyde a higher boiling/melting point.
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