Re: Finding concentration of caffeine

Mark wrote:
> A student wants to find the concentration of caffeine in coffee beans.
> We have a method of extraction, using ethyl acetate. Anyone know of a
> simple way of determining the concentration of the solution produced.
> We are a small school with limited apparatus so suggestions such as
> HPLC, Mass spec and UV spectroscopy are not an option ... although we
> do have things like burettes, colorimeters and a finite budget!
>
> Thank you
> --
> Mark

Hmmm...tricky. So you want "quantitative wet chemistry analysis of
caffeine". Well, if you plug that into google, the first link is:
http://www.newton.dep.anl.gov/askasci/chem00/chem00291.htm Their plan
looks like it would work, but I'll leave it to you and your student.

I find it hard to fight the urge to shoot out an opinion here: What's
the point? Seriously, we have instruments to do these analyses these
days. You're expected to develop a proficiency in the use of these
instruments as part of an education in chemistry, generally at the
university level. Maybe the kid thinks dabbling with all these
chemicals is somehow counts as learning something. And maybe teachers
want to reward the initiative, so I don't want to discourage too much.


But this is like using traditional blacksmith's tools to build an
automobile, then displaying it at the Renaissance faire. Only total
geeks would care, and maybe not even them.

.

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