jamit
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distillation problem - toluene sodium benzophenone
so I've been drying toluene using the sodium benzophonene method. I first refluxed with sodium metal for one day. Next I've put in 5g of
benzophonene and reflux for another day until the all water was destroyed -- indicated by the blue-green color of benzophonene complex.
Now I'm trying to distill it using simple distillation but I can't get the toluene to come over. It just boils and boils but the temp isn't getting
past 60C. I've been at it for 5 hrs and nothing is coming over. what am I doing wrong and why is toluene not coming over?
Any idea?
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anewsoul
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That's weird. Is the toluene condensing before it gets to the condenser so that it just refluxes? Have you tried insulating the still head?
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jamit
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is it possible that the benzophenone reacted with the toluene because the final liquid is transparent light yellow with sodium metal and dark blue
complex at the bottom of the flask. It's not even going up the condenser but it's boiling for at least 4 hrs. I have distilled OTC toluene before
and never had this problem. but i thought I try drying the toluene using the well known method of sodium benzophenone but now I'm stuck wonder why
its not distilling over the dry toluene??
I must be missing something. I can only think that there was a reaction between the toluene and benzophenone?
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JJay
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What is the temperature inside the boiling flask?
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DraconicAcid
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I think you just need to insulate the still head. I've dried toluene that way many times, and never had a problem.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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