Having Fun with Chemistry L. A. McGrew University of Northern Iowa. Cedar Falls, IA 50614 For several years, the Chemistry Department of the University of Northern Iowa has sponsored the "UNI Chemistry Olympics," a program in which high school students compete with each other in performing chemical experiments and calculations. Our goal has been to promote chemistry and to stimulate the study of chemistry among high school students. The program has also enabled us to make personal contact with public school teachers and students and has increased our rapport with that important branch of the field of chemical education. Our olympics program is held on a Saturday late in the school vear. . . which helos first-vear chemistrv students feel more comforht~lt:with pmicipating. A general announcement of the date is made in the iail. with a call for reristration in January. Preregistration is required, since this allows us to nlan most effectivelv and lessens the chance for cancellations bn the day of the event. A significant feature of our olympics is that all competitive events are described in detail when registration is sblicited. This allows plenty of time for student preparation and makes the program effective as a learning stimulus. Our facilities allow participation of u p to 40 students. Typically, 10 to 12 different high schools are represented. We have one class of competition and make no distinction between high school juniors and seniors or between fist-year and second-year chemistry students. The time for preparation, made possible by the advance notice, exerts a "leveling" effect on the competition. We try to keep the emphasis on having fun with chemistry, rather than on winning. Both individual and team events have played an important oart in our oroaams. Descri~tionsof some events of each t w e Hre found at &e end of this article. No particular claim bf orieinalitv is made for anv of them. Most of the events are haled on iaboratory conceits and operations. Excitement is created in some of the events, such as qualitative analysis, by making time a factor in choosing the winner. We have emphasized team competition in planning our most recent programs. A team size of three students works well. Most students are less apprehensive and self-conscious in team competition. The te& approach also relates better to the way chemistry is actually done in major laboratories. 'l'eachers~artirula& enjoy helping their teams with advance preparations m d watching the uutcume un olvmpics day. Comhinine an individual chcmistrv examination event with - ~ - -~~-~~ about five team events provides a full day of competition. Each entrant receives a certificate of ~ a r t i c i ~ a t i o nand . members of lirst and second place teams in each event receive ril~hons.For the overall cumuetition. first and second d a c e teams are also identified and the schkls of these teams receive ~ r i z e ssuch as triole-beam balances. larae, - ~. l a s t i cperiodic charts. and demonstration molecular m~rlels.Electronic calculators and cooies of the "CRC Handtlook of Chemistw and Physics" are good prizes for winners of individual eve&. A successful olympics program requires a significant commitment of faculty time. A departmental committee of five has supervised the development of competitive events, rules, and preparation of materials. Ten faculty members have been
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Presemed at lhs 1851hAmerican Chemical Society National Meeting. Seanie. WA, March 23, 1983.
used to supervise and judge the events on the dav of comoetition. t he purchase of prizes and other necessary materials has been supported entirely by alumni contributions to our account in the University of Northern Iowa Foundation. The Admissions Office has generously provided lunch tickets for use by all entrants in u&ersity d&ing halls. One final note. We require student entrants to he accompanied by their chemistry teachers. Teachers are permitted to view team events, and we also try to provide some activity just for them. Programs on the handling and disposal of hazardous chemicals, preparation for college chemistry, classroom demonstrations, and demonstrations of new instruments have met with interest. individual Events 1) Titration-Each
entrant will determine the normality of a hvdrochloric acid solution bv titration with a standard sodium hvdmxide solution of known cuncentrat:un. All necessary materials will be provided at each t.ntrant', statiun. The determination may he repeated to a maximum of four values. Thirty-minute time limit. 2) Preparation of a Solution-Each entrant will be provided with a sample of a pure compound. From this sample, an aqueous solution of concentration specified hy the judges will be prepared. Pipets, volumetric flasks. and a balance will be orovided. The winner will be the entrant mmi& closest to the soeeified concentration. 3) Chemicol Formulat and E q u n t # r . o - This i* an examination I I chcmial nmesgiven, event.There will IIL. three types ot'questio~~s: supply formulas; 2) chemical formulasgiven, supply names; 3) balance chemical equations. Oxidation-reductionequations will be included in the last part. Thirty-minute time limit. 4) Molecular Models-Each entrant will be provided with a set of "ball-and-stick" models and with the names of five organic comnounds. IUPAC names will be eiven and the comoounds will be from the alkane, alkene. slkyl halide, and alrrnhd funilie*. Enrrnnt wdi auaemhle models 3 0 nri t g n have five conlplete mudcli when finished The winner will he d~tarminedon the basis of correctness uf construction and time for completion. Notes. In the solution event, we specify a concentrationso low that dilution of an original stock solution is required for good results. We use a colored solute so that results can auicklv . , be determined soecrruphatumetrirnlly.This also works as a team event and ha, proven t o t w one of the mort dfficuir. 'l'he molecular mudel, "bent will mrasurrmly mnnunl dcxtrr~tyunles9some fairly difficult rlamQSWe used Team Events 1) Osmotic Pressure Raee-The object of this event is to produce
a solution that will dialyze most rapidly. The winning team will be determined by measuring time taken for the solution to rise 20 cm in a tube of 6-mm diameter. Teams will be provided with glass tubes, dialysis tubing, and stoppers for connection. Each team should supply about 1W ml of a solution of choice for dialysis. Samples of the dialysis tubing will be sent upon request. 2) Maximum Density-The object of this event is to prepare an aqueous solution of the highest density. Teams should supply the compounds they plan to use as solutes. More than one solute may he used. Teams will he given 20 min to dissolve their solutes to produce a solution, not asuspension. Heating will not be allowed.At the end of the 20-min period, a 25-ml sample will be taken and its density will be determined by the judges. 3) Lowest Temperature-The object of this event is to produce the coldest aqueous solution using materials initially at room temperature. Teams should supply materials, solids or liquids only, planned for use as solutes. Judges will furnish glassware and water at room temperature. Expanded polystyrene cups will he used to contain the mixtures. Temperature will be measured by the judges Volume 61 Number 6 June 1984
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a t the end of the 30-min event period, or earlier if requested by a
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4, Humemadu Y%rrrn,,mrt~r--Earhtram will design and construct 3 thermumeter to Ire used ill mrnsurinr the temperature o t a solution rupplwd by thr ludger. The thermometer must t w a n expansion type. No mercury may be used. The temperature to be measured will be in the range 0-50 'C. Design of the thermometer should he such that it can be used with asample supplied in a 100-ml heaker. The team coming closest t o the actual temperature will be the winner. 5) Homemade Spectroscope--Each team will design and construct a spectroscope t o be used in measuring the wavelength of an emission line in the visible spectrum. A source for theline will be provided by the judges on olympics day. The wavelength scaleused in the device must have been constructed and calibrated by the team members. The measurement will be made under the normal illumination conditions
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of the laboratory of the event. The team coming closest to the actual wavelength wins. 6) Qualitotiue Analysis-Each team will he provided with seven numbered solutions in test tubes and a list of the eamoounds conLaitled in thvsr solution*. l.itmw pnper,dlstill~dwater, and nmmal ittmr used in teeing will be auppl~rdhy theludges Each team suill determine the identity of the compounds in solution in the tubes. No refills will be given. The team identifying all compounds correctly in the shortest time will he the winner. 7) Buffer Preparatron-Each team will prepare a buffer solution of pH specified by the judges. The specified value will be in the range 4-10. Each team will prepare the solution by mixing appropriate amounts of premixed solutions which the team supplies. A maximum of six such solutions is allowed. Judges will supply valumetric glassware and other supplies needed t o complete the event. The team coming closest t o the specified pH will be the winner. ~
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