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Chemistry Forums for Students => Analytical Chemistry Forum => Topic started by: hannibal on June 25, 2005, 01:09:11 AM

Title: analysis in esterification
Post by: hannibal on June 25, 2005, 01:09:11 AM
i am carrying out acid catalysed esterification reaction of acetic acid and ethyl alcohol.for the analysis of reaction mixture can i analyse simply ethyl alcohol and water using a GC and find out the concentration of ethyl acetate and acetic acid by stoichiometry of the reaction.i already have my gc calibrated for ethyl alcohol and water and dont want to take the pain of calibrating it for ethyl acetate and acetic acid
Title: Re:analysis in esterification
Post by: lemonoman on June 25, 2005, 03:46:51 PM
In THEORY this would work...unfortunately, the real world isn't as kind.

I think it depends on a lot of factors:

Firstly, if you analyse the remaining reactants instead of the products directly, you have to be EXTREMELY careful about how much you put in to begin with.  Depending on the GC apparatus you're using...it could be as sensitive as picograms - which is a VERY difficult sensitivity of get measured at the beginning.

Also, depending on what kind of GC apparatus you have (you may have just a GC-FID, maybe a GC-MS, GC-TOF-MS, GCxGC-TOFMS) then that should factor in your decision as well.

Final comment: I'm not familiar with calibration of GCs...if it was me, I'd be running a few GC runs with Standard additions