edited bv
tested demonstrcrtions A Chemistree Submined by Steven Murov Engineering, Mathematics, and Physical Sciences Division Modesto Junior College 435 College Avenue Modesto, CA 95350 Checked by
James ~iewahner honhern Xenl~ckyUn verslly Hgnano rlegnts, K Y 41076-1448
The wonderful proliferation of entertaining and educational science oresentations for families has presenters always on the liokout for dramatic finishes. AS the holiday season is a common time for these presentations, it is fun to close with a holiday theme. In preparation for the hosting of a local amateur demonstration night modeled after a n excellent event a t the 1993 Kansas City NSTA Conference', it occurred to me that the absurd and fascinating electrocuted pickle demonstration (1, 21 could provide a dramatic climax to the evening's presentations. A chemical Christmas tree or 'chemistree" was constructed from a ringstand and clamps similar to the one illustrated by A. W. Sturges (31. However, in contrast to the earlier "tree", our clamps were used to hold only test tubes and 50 mL round bottom flasks. Each test tube or flask was filled with a fluorescent solution or in one case a detergent with a brightener that fluoresced. Aqueous solutions of fluorescein, salicylic acid (or sodium salicylate), and rhodamine B2 work nicely and avoid use of the organic sol-
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Journal of Chemical Education
GEORGE L. GILBER; Denison University Granville. OH 43023
vents required for nonionic organic fluorescent compounds. Soda water containing quinine or drug store quinine products also fluoresce impressively. Before mounting the flasks, the ringstand and clamps were spray painted with a green fluorescent paint available from a r t and hobby stores. Awhite lab coat was washed with a detergent containing a fluorescent brightener (to give the whiter than white look) to be used a s the snow base. A small amount of tinsel was draped on the clamps to give more of a Christmas tree look. Five clamps were left empty to be loaded with dill pickles immediately before use. A black or long-wavelength ultraviolet light was mounted a t the base of the "chemistree". Immediately before use, five pickles were mounted into the clamus. Five electrical cords were meoared bv cuttine the recedtarle ends offof five inexpen&ebxtensibn cords; solittine t h still ~ iniiulated wirc do\vn almut 4 in. and a~ldcring a l k sheetmetal screw onto each wire. The two leads were then inserted into ou~ositeends of a uickle. The screw modification works b e t t e i k a n nails, wh& occasionally fall out duriw oceration and Dose shock hazards. The . uotential . use of f&s instead of nails or screws has a l ~ been o suggested 12,. The five pluzs are inserted into a six-ulup mulriple outlet containing aswitch. Although we have Aot experieked any fuse or circuit breaker problems, a subsequent test revealed that pickles draw as much as 5A. Therefore it would probably be advisable to use two separate circuits with a maximum of three pickles per circuit. Demonstration The "chemistree" is brought in covered by the lab coat. The room is darkened and the tree unveiled and the lab coat is wrapped around the base of the tree. The black light
causes most of the tree to fluoresce i n different colors. For the climax, the multiple outlet is turned on. After a short initiation period, all of the pickles should light up. The longer the time t h a t t h e pickles a r e electrocuted, t h e greater t h e production of a rather unpleasant burning pickle odor. Because of this, the demonstration should only be left on about a minute. Variations such as other kinds of pickles or wiring the pickles i n parallel have not been tried in our lab. Perhaps a contest for the Guiness Book of World Records could he held for the greatest number of pickles glowing a t one time. The electrocuted pickles have even inspired one member of the audience to make buttons including "save the pickle", "pickle power", and "nuke the cuke", and a song called "Oh, Chemistree", has been written to accompany the music of Oh, Christmas Dee.3
Literature Cited 1. Reese. K M. Chem. ondEng Netus 18'31 (No". 18).68. 2. Appling, J. R.:Yonke, F J.;Edgington, R. A,: Jaeoba, S.:Jones, R. F J Ckem. Ed=. 1993.70.250. 3. Sturges, A. W. J. Chem. Educ. 1956.33, A547,626,
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'For a aescr pt on of 1h1sevent see tne d scuss on of the M cnae Faraoay Grand I Lmlnal on Compel t on' In Ihe Dec 1993 Jan 1994 issue of NSTA Reports, page 13. 'Caution: Rhodamine B is a suspected carcinogen and gloves should be worn when handling it. Some of the solutions decompose within days and fresh solutions should be available. 3l want to thank Wes Page of the Modesto Junior College Media Department for sharing these puns with me and Allen Boyer and Stephen Stroud of the Modesto Junior College Music Program for helping with the song.
Volume 71 Number 12 December 1994
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