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Topic: Thin Layer Chromatography - What Order?  (Read 11304 times)

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Yossarian

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Thin Layer Chromatography - What Order?
« on: October 22, 2005, 03:37:22 PM »
I'm not sure about my answer to this question, so I was hoping I could get some help on this forum.

In what order (from top to bottom) would you expect to find naphthalene, butyric acid, and phenyl acetate on a silica gel TLC plate developed with dichloromethane?

I would say that naphthalene would be at the bottom, since it is polar, and phenyl acetate would be at the top, with butyric acid in the middle.  Can anyone tell me if this is correct, and if not, explain what is correct and why?  Thank you in advance.

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Re:Thin Layer Chromatography - What Order?
« Reply #1 on: October 22, 2005, 04:09:42 PM »
What makes naphthalene so polar?
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Yossarian

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Re:Thin Layer Chromatography - What Order?
« Reply #2 on: October 22, 2005, 04:17:04 PM »
Excuseme, because naphthalene is nonpolar.  I simply mistyped, sorry for my mistake!

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Re:Thin Layer Chromatography - What Order?
« Reply #3 on: October 22, 2005, 06:34:53 PM »
Polar liquids will stay at the bottom of the TLC.
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Re:Thin Layer Chromatography - What Order?
« Reply #4 on: October 23, 2005, 04:37:52 PM »
In my experience, carboxylic acids are very difficult to move on silica gel without adding some acid to your eluent liquid, typically acetic acid.

Yossarian

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Re:Thin Layer Chromatography - What Order?
« Reply #5 on: October 23, 2005, 04:41:21 PM »
Mitch,

After doing some more reading and thinking on the subject, I realized you are correct.  I guess this now means that naphthalene will be at the top, phenyl acetate would be in the middle, and butyric acid would be at the bottom.  Is this now correct?

Thanks for your *delete me*

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Re:Thin Layer Chromatography - What Order?
« Reply #6 on: October 23, 2005, 05:27:51 PM »
Well, since you've done the additional reading. You don't need us to hold your hand. ;)
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