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Philip 5. Bailey,' Christina A. Bailey, John Andersen, Paul G. Koski, and Carl Rechsteiner California Polvtechnic State University Son Luis Obispo, 93407
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Producing a Chemistry Magic Show
Each spring Cal Poly has an academic open house called Poly Royal. It is a two-day affair in which the students and faculty of each department present demonstrations and displays illustrating their study areas to the public. An important part of the chemistry department's presentation is a magic show.2 It has proved to be of universal appeal and scientifically stimulating to young and old alike. Over the past six years, over 20,000 have attended these shows, proving its popularity. We have expended a great amount of time and energy in testing, improving, and developing a variety of tricks and adapting directions which are reliable especially when large batch quantities of reagents are needed. Most of the instructions we present here are for the presentation of a single show and can he scaled u p proportionately. A heavy schedule of shows such as we have a t Poly Royal (every 30 min, 10-15 performances per day) is possible if the bulk reagents are stored in the show room with a closely located work room for preparing hydrogen balloons and liquid nitrogen for the next shows. Hydrogen Balloons 2H,
+
0,
name
NH,SCN + FeCI, Colorless
Hard Water-Fire
+ energy
2H,O
-
K,Fe(CN), + FeCI, Colorless
F~(scN),~
Red Fe,(Fe(CN),), Blue
Our greeting to the public is painted on a large sheet of Whatman -1 paper with 0.1 M ammonium thiocyanate and 0.1 M potassium ferrocyanide, both colorless. The message "appears" when the sheets are sprayed with 0.1 M ferric chloride. Reagent conceutrations can be varied for color preference. The posters can be prepared a few days ahead of time and should be thoroughly dry before stacking. Liquid Nitrogen A 1- or 2-1 wide-mouthed Dewar flask is filled twothirds full with liquid nitrogen. This is the basis for quite a few cryogenic demonstrations. At least a dozen air inflated balloons can he condensed into the flask before the show. During the performance a few more can be added and then all are removed with tongs and allowed t o expand. It is particularly effective to condense a large tied and twisted balloon figure. A banana is frozen in the liquid nitrogen for at least 1 min. It is then used to hammer a nail into a balsa wood board. Use asbestos gloves to handle any frozen objects. 524 / Journal of Chemical Education
Water
Saturated Ca(C,H,O,),
+
CH,CH,OH
-
gelpsterno")
Forty milliliters of a saturated calcium acetate solution (150 g Ca(CzH3O2)~in 500 ml of water; add enough NaOH to make the solution slightly basic to phenolphthalein) is poured into a 400-ml beaker. A second 400-ml beaker contains 300 ml of ethanol with about 2 ml of phenolphthalein. Pour the colorless ethanol into the colorless calcium acetate solution. The mixture is poured hack and forth until the pink gel forms (sterna). Turn out the lights and light the gel. Lemonade tannic acid
Medium to large balloons are filled with hydrogen gas shortly before each performance, tied to strings, and floated 5-8 ft above the demonstration table. A candle on the end of a 3-m stick is used to explode them throughout the show, preferably in a darkened room. Welcome Posters
A flower such as a rose, chrysanthamum, or carnation can be frozen and shattered. A hollow rubber hall such as a Pennsy Pinky can be immersed for 30-60 s. Be sure to rotate the hall for uniform cooling. The ball can then be shattered against a wall.
+
FeCI,
-
blue complex
Yellow
%SO.
complex destroyed
A stock solution of tannic acid is prepared by dissolving 50 g of tannic acid in 400 ml of water. Set u p a 2-1 flask (or large glass pitcher) and six 400-ml beakers (or glasses). It is important that the beakers he kept in order, preferably by numbering them. Pour 15 ml of stock tannic acid solution into the 2-1 flask and fill three-quarters full with water (vary quantity of tannic acid so that a pale yellow color is evident after dilution). Beakers 1, 3, and 5 will remain empty. Place one drop of saturated FeC13 solution into beaker 2. Cover the hottomsof heakers 4 and 6 with concentrated HzSOI. The trick is done in two parts using beakers 1-3 and 4-6, respectively. In the first part, "lemonade" poured into heakers 1 and 3 remains "lemonade" while that poured into beaker 2 hecomes "grape juice." All three beakers are then emptied back into the 2-1 flask which becomes "grape juice." In the second part of the trick, the "grape juice" becomes "lemonade" when poured into heakers 4 and 6 and remains "grape juice" in beaker 5. All three heakers are then emptied back into the flask which, of course, becomes "lemonade" once again. The procedure is visually effective when the heakers are filled in order. Synthetic Gold Clock 2As0,- + S,03'- + H20 clear
clear
-
2~~0:-
+
2s
+
2 ~ '
gold
To whom correspondence should be addressed. In addition to the authors many other faculty and students at Cal Poly have made significant contributions to the magic show. Some of these tricks were originally described in L. A. Ford's "Chemical Magic," Fawcett, New York.
Prepare the following two solutions: Solution A-dissolve 3 g of sodium arsenite (NaAsOa) in 150 ml water and add 16.5 ml glacial acetic acid; Solution B-dissolve 30 g of sodium thiosulfate (NazSz03) in 150ml water. Pour 150 ml each of solutions A and B into separate 500-id Erlenmeyer flasks. Comhine the solutions. A gold color will appear in approximately 30 s. The length of time for reaction can he increased or decreased by decreasing or increasing the concentrations of the reactant solutions, respectively. Iodine Clock 10,-
I,
Volcano
green
orange
+ 3S0,2-
+ starch
--c
--c
1-
+
3S0,1
blue-black complex
Prepare the following two solutions: Solution A-dissolve 0.25 g potassium iodate in 150 ml of water; Solution B-dissolve'O.1 g sodium sulfite, 0.5 ml 6N Has04 and 8 ml 1% starch solution (1 g potato starch in 99 ml hot water) in 142 ml of water. Place 150 ml of solutions A and B into two separate 500-ml Erlenmeyer flasks. Pour one solution into the other. The resulting mixture should turn black in about 15 s. Increase or decrease the reagent coocentrations to vary the length of time for reaction. Burning Handkerchief C,H,OH
0
name
CO,
+
Fill a 100- or 150-ml heaker with granular ammonium dichromate. Pour the solid in a mound onto a large asbestos pad. Wet the top of the mound with a few milliliters of acetone and ignite it. The green product occupies a much greater volume than the starting material. "Cup and a Half" of Coffee
coned
C,,H,,O,,
HZS04
+
12C foam
11H,O steam
Fill a 150-ml heaker just less than half full with granulated sugar. Add about 40 ml of concentrated HzS04 and mix thoroughly with a glass stirring rod for approximately 2&30 s. Guide the carbon foam with the stirring rod. Smoke Puff
H20
Place ahout 75 ml of a 50:50 ethanol-water solution in a 250-ml beaker. Thoroughly soak a cotton handkerchief in the solution. Hold the handkerchief with long tongs, ignite it, and allow it to hurn in a darkened room for about 30 s, Extinguish the flame with a fire extinguisher. The handkerchief remains undamaged. Cold Light of Lumino13 NH, 0
I
the layers do not mix. Using a copper wire with a small hook carefully draw out the nylon film which forms a t the interface of the two layers. A single strand u p to 40 ft long can he pulled out. The following tricks should he performed at the end of the show because they produce noxious fumes and smoke.
Place henzoyl peroxide into a 7-dram vial or a test tube to a height of 0.5-1 cm. Support the vial and add one drop of aniline. In about 15 s a puff of smoke will rise to the ceiling. Red Spontaneous Fire
II
2KC10, Blue Cbemiluminescence H2OZ an*
0 Prepare the following two stock solutions: Solution A-dissolve 1 g of luminol (5-amino-1,4-phthalazdione) and 50 ml of 10% NaOH in 450 ml of water; Solution B-make 500 ml of a 3% potassium ferricyanide solution (3 g K3Fe(CN)e per 97 g of water). Pour 50 ml of solution A and 350 ml of water into a 500-ml heaker. Into a second heaker pour 50 ml of solution B and add 350 ml of water and 3 ml of 30% Hz02. Darken the room and pour the two solutions simultaneously through a large funnel into a 2-1 flask which contains a few crystals of potassium ferricyanide. The hlue-green light produced can be rejuvenated temporarily as it begins to fade by adding small amounts of dilute base. This demonstration is sensitive to the strength of peroxide. Some minor experimentation in the quantity and concentration of peroxide to add may he necessary. Nylon Rope
Pour 25 ml of a water solution which is 0.5 M in hexamethylene diamine and 0.5 M in NaOH into a 100-ml heaker. Then carefully pour down the side of the heaker 25 ml of 0.25 M adipoyl chloride in cyclohexane. Be sure
C,,H,,O,,
+
0,
-
2KCI C
+
+ 30, CO,
+
H,O
Fill a 5-dram vial with potassium chlorate and cap. Fill a second 5-dram vial with granulated sugar and add about 0.5 g of strontium nitrate. Cap the vial. The vials can he stored in a 150-ml heaker until show time. When ready to perform the trick (not before) mix the contents of the two vials together thoroughly in a clean, dry heaker with a clean, dry stirring rod. Place 1-3 ml of concentrated HzSO4 on an asbestos pad, darken the room, pour the mixture over it, stand hack. After a brief crackling, an intense red flame is generated. Green Spontaneous Fire
Weigh 4 g of zinc dust into a dry l-dram vial. Into a dry 7-dram vial weigh 4 g NH4N03, 1 g NH4C1, and 0.5 g Ba(N03)z. When it is time to perform the trick (not hefore), pour the zinc into the other vial, cap it, and vigorously shake the materials to ensure thorough mixing. Pour the gray mixture onto an asbestos pad and sprinkle a few drops of water onto the mound (can be done with the shaking of wet fingers). A green fire erupts spontaneously. Although the tricks described are spectacular in themselves, the showmanship of the magician and his assistants greatly enhances the performance. Also, the use of appropriate costumes and room decorations add to the spirit. Be sure all performers and assistants wear safety glasses. ZFieser, L. F., "Organic Experiments," D. C. Heath & Co., Lexington, Mass. Volume 52, Number 8. August 1975 / 525
