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Topic: Identification of Unknown Compounds  (Read 1641 times)

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Offline durianguy

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Identification of Unknown Compounds
« on: March 30, 2016, 10:37:46 AM »
Hi everybody,

I'm new here.

So I have this experiment that I am doing. I am given an unknown with 2 compounds in it. But I'm not sure whats in the compound.
The compound looks like it has both liquids in it. But I see some particles in the liquid, so I'm not sure. Also when I leave some of the compound out
in the hood (or bench) I see that it becomes this white chalky substance. Does this mean that I have a liquid and a solid in my unknown? And how can
I determine this? By boiling the unknown?

Thank you!

Offline durianguy

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Re: Identification of Unknown Compounds
« Reply #1 on: March 30, 2016, 10:44:08 AM »
Sorry, I meant. Do I have to evaporate the unknown?

Offline TheUnassuming

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Re: Identification of Unknown Compounds
« Reply #2 on: March 31, 2016, 07:58:51 AM »
What have you covered in the class so far with respect to isolation and characterization of compounds?  I'm assuming this is a sophomore organic chemistry lab?
When in doubt, avoid the Stille coupling.

Offline durianguy

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Re: Identification of Unknown Compounds
« Reply #3 on: March 31, 2016, 10:57:06 AM »
Thanks for answering!

So I believe it would be an acid base extraction because it would be considered a solid and a liquid combination.

Offline TheUnassuming

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Re: Identification of Unknown Compounds
« Reply #4 on: March 31, 2016, 12:43:29 PM »
Acid/base extraction can work just as well if both of your unknowns are solids and just happen to be in solution.  In any case, extraction could definitely work depending on what the unknowns are.  Try it on some of your sample to see if you get anything interesting.  Just be careful rotovap'ing your organics if you think one of your unknowns is a volatile liquid. 

If you think one is a solid and one a liquid that easily evaporates, could you do a distillation?
When in doubt, avoid the Stille coupling.

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