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Homework Help: GC help

  1. May 17, 2010 #1
    1. The problem statement, all variables and given/known data
    How would you use chromatography to determine whether an unknown pure liquid is 1-pentene, cis-2-pentene, or trans-2-pentene?


    2. Relevant equations



    3. The attempt at a solution
    I looked up the boiling points of the three and see that 1-pentene is lower, but the cis and trans pentene are similar. This is where I am stuck.
     
  2. jcsd
  3. May 18, 2010 #2

    Borek

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    Staff: Mentor

    I can be wrong, but seems to me like best method would be to compare retention time with known sample of substances in question. When you have a single substance and no reference, determining what the unknown is is like reading the dregs.
     
  4. May 18, 2010 #3

    chemisttree

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    Science Advisor
    Homework Helper
    Gold Member

    The title is "GC help" but the question doesn't specify that you utilize gas-liquid chromatography. Also, GC separations are largely a function of BP but polarity plays a part as well.
     
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