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Homework Help: How to distinguish between pairs of componds?

  1. Jan 11, 2009 #1
    1. How to Distinguish between pairs of componds below?

    i. sodium stearate and dedecylbenesulphonate
    ii. trimyristin and myristic acid
    iii. beewax and paraffin wax
    iv.trimyristin and trioleon

    2. The attempt at a solution
    i. treat with Na, sodium stearate react with Na form calcium stearate, but dedecylbenesulphonate will not form calcium stearate

    ii.saponification, treated with KOH, trimyristin form 1 glyrerol and 3 myristic acid( but don't know how to distinguish it from the observation of the chemical test during experiment); myristic acid will not undergo saponification do not have any observation change

    iii. saponification, treated with KOH, beewax will not have any reaction ; paraffin wax do not undergo saponification

    iv.saponification, treated with KOH, trimyristin form 1 glyrerol and 3 myristic acid, triolein form 3 oleic acid
    Last edited: Jan 11, 2009
  2. jcsd
  3. Jan 11, 2009 #2


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    Staff: Mentor

    You just don't ask. You try, you tell us what you did, we push you in the right direction.
  4. Jan 11, 2009 #3


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    Homework Helper
    Education Advisor
    Gold Member

    From xiaofupo:
    Is this for school or for business?

    i. Could you make a practical investigation of use of ion-exchange chromatography? Which salts are soluble and which are not?

    iii. What does each of those waxes alone smell like? One of them comes from petroleum and may or may not have one kind of odor; the other comes from bees and it certainly has a certain odor (smell a sample of bees wax and you will know what it is). I wonder if melting point could be useful here, too. Maybe hardness measurement (mechanical, not the "hardness" of calcium & magnesium in water - that is a completely different meaning for hardness).
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