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Homework Help: Volatility of aldehydes and ketones

  1. Dec 22, 2011 #1


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    1. The problem statement, all variables and given/known data

    why aldehydes more volatile than ketones

    2. Relevant equations

    3. The attempt at a solution
    I would have presumed that as BOTH contain the same C=O group the overall polarity of the molecule would be the same. hence the strength of the dipole forces should be the same
    As they have the same no. of electrons so London forces are the same

    their surface area's are the same so there should be no difference in surface contact??

    what causes the slight difference (It is only a slight difference!)
  2. jcsd
  3. Dec 22, 2011 #2


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    Homework Helper
    Gold Member

    For a moment you had me worried - I didn't realise they were.

    But as you say, only slightly, so that's OK. :biggrin:

    I guess in a ketone there are two inductive pushes to polarise the C=O and just one in an aldehyde. You could also think about these factors in connection with a possible role of keto-enol tautomerism, I do not actually know the answer but that could start you looking into things.
  4. Dec 22, 2011 #3


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    ye I figured.
    given you didn't know it happened how could you know why
    never mind!
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