Unit 5.6 Mixture Design and
By separating the components of colored markers using chromatography,
students gain insight into how the markers are designed
and made. Chromatographic methods are used in industry and
in research for a wide range of analyses and design.
Video program cues: 44:05-57:25
Separating mixtures laboratory
Veatta Berry teaches her students about solvent separation
through paper chromatography of markers.
JCE Editorial Staff (2000)' The Write Stuff: Using Paper
Chromatography to Separate an Ink Mixture, 'Journal of
Chemical Education, Vol. 77, No. 2, pp: 176A-176B.
"We are using chromatography not only
for inks. In the same way inks separate, drugs separate
as well. If you have heroin, cocaine, and codeine
those are all alcohol-type drugs. You can run them and they
will separate. We use larger TLC plates for drugs because
we want them to run a longer distance. In drugs its
a single compound, and you will need a longer plate so it
will separate in the correct shape. Now you can identify
drugs with mass spectra, but we need to have a known to
run with it, and the known we identify on a TLC plate. Just
because a new technology comes out, doesnt mean that
this doesnt work any more. We use it because it works."
Chemist, FBI Explosives Unit
Long, G.A. (1995)' Simulation of a Forensic Chemistry Problem:
A Multidisciplinary Project for Secondary School Chemistry
Students, 'Journal of Chemical Education, Vol. 72,
No. 9, pp: 803.
"The beauty of chemistry has always
been that there is an infinite number of ways that you can
connect molecules. And we have not yet gotten close to getting
all of the combinations. This is where the field of combinatorial
chemistry comes about. That explores the many different
ways to connect the different atoms to give you materials
with different properties. Its back to basic chemistry.
Sticking together balls and sticks. If you can do that in
your hand with balls and sticks, you can do that on the
molecular level, because the rules of engagement are well
known. How you put them together is only controlled by your
Dr. Richard Wool
Professor of Chemical Engineering, University of Delaware
to Workshop 6