in this issue A Winter's Entertainment, Vlll
Chromatography for the Precollege Student (and Anyone Else Curious about the Natural World)
It has become a Journal tradition to collect, in the December issue. those contributions that are on, first dance, entertainment pieces, but which, on closer inspection, have oedaeoeic value. This vear's collection contains anotherAinst&&ent of "The Chemical Adventures of Sherlock Holmes" by Waddell and Rybolt (page 999) in which Holmes must use his skills as an analytical chemist to deduce the cause of the sudden mood swings of a usually congenial stepfather. Another exercise has& on a fictional character is Brisbois's "Davidsoniana Jones" (Daze .971) whose adventures are modelled on a cross between an Indiana Jones movie and a computer game but whose purDose is to teach organic chemistrv students to use the curved arrow formalism correctly. bunding out the literary contributions is a historical note by Sutter (page 998) offering another poem on the "intifinite progression of fleas" concept. Puzzles and games are particularly suited by their nature for teaching information that is otherwise tedious to learn-such as numerical values or relationshi~sthat must be memorized. Helser's "Metric Matrix" puzzle (page 986) is a prime example; while students are fmding the correct wav to assemble all the sauares.. thev " are familiarizing themselves with the relationships among metric units. Similarly, Thomas's "Elemental Anagrams" (page 984) are an entertaining way to review the names for the elements, and Helser's amino acid rebuses cover basic hiochemical reactions. Crawford (page 966) presents a crossword puzzle whose primary purpose is to entertain, but whose correct solution provides an interesting historical quote that will seem very apt to the modem student (and even, perhaps, the practicing chemist). While not strictly part of the Winter's Entertainment, several other articles in this issue can help teach concepts in a way that holds student attention. As always, the ~ a e e1028) and Overhead Tested Demonstration feature (.. Projector Demonstrations (pape 1024) provide excellent materials for showing studinis actual chemical phenomena in the lecture hall. Yamana (..~ a e 964) e contributes another in his series of geometric models that can be made from an envelope, and~illiams(page 985) provides a visual aid and mnemonics to h e h students learn the details of the Krebs cycle. Finally, Shaw, Greenier, Lasca, and Brooks (page-1020) desciibe a successful program in Wisconsin that reaches wmmunitv audiences and both entertains them with and informs them about scientific subjects.
The experience of the presenters in the program discussed in the previous paragraph would indicate that there are many citizens, young and old, who have a keen curiosity about scientific matters. Chromatography is one topic that should be particularly appealing to these people: The results are often spectacular, and a variety of scientific principles can be illuminated. A series of papers in this issue use some form of chromatography in activities that range in suitability from elementary school through high school. The colorful results of paper chromatography lend themselves to activities for the very young or for public outreach programs where the novelty will attract participant's attention. Buccigross (page 977)takes the familiar chromatography of marking pen ink and performs it on T-shirts instead of Daoer. ~rovidinestudents with science in a DODular and &ahe firmat. ~ i c k e rIhde, , Cox, and sari& ( ~ a e 979) e a d a ~the t idea to radial chromatoera~hv.usine h k i to p;oduee flowerlike designs both o n - ~ - i h i kan; paper that can be used for decorative purposes (this month's cover shows some of the more colorful results of this latter process). Four chromatography experiments that are particularly appealing for the secondary school laboratory are presented in this month's Filtrates and Residues column. Kimbrough (page 987) offers an inexpensive alternative for the column chromatography of leaf pigments, helping those with limited budgets. Similarly, Reynolds and O'Dell (page 989) have adapted thin-layer and column chromatography procedures and equipment to fit the time, budget, and space restraints on the secondary school laboratory The novelty of separating the dyes used in M & M candies helps Kandel (page 988) show how chromatography helps solve important questions about food purity. As part of a program to introduce students to industrial research, Wigman and Kelsch (page 991) have developed an activity that can be used at the beginning of a tour to show the basic ideas of chromatography underlying the automated GC and LC equipment used in the research lab. Sizeexclusion chromatography is seldom discussed even at the introductory college level because of the more difficult nature of the process. McLoughlin (page 993) has devised a simple demonstration and laboratory experiment that first explains the concept and then allows students to apply it. For those who wish to attempt a more ambitious project with their students, Bird and Sturtevant (page 996) present an apparatus design and procedure for the column chromatographic separation and extraction of five FD&C dyes.
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Journal of Chemical Education
