Role-Playing in the Quantitative Analysis Lab James P. Deavor College of Charleston, Charleston, SC 29424 Role-playing analytical laboratory courses have recently been described for iunior and senior level courses (14). This article describes a role-playing course that has been used in the sophomore level quantitative analysis laboratory by employing experiments that are currently used in the traditional lab seaueuce (6). Teamwork has been described a s being "the challenge of the nineties'' (7).Incorporating this approach into lower level laboratory courses would help to educate students earlier about how "real" chemistry is done, by chemists working as teams and not a s individuals working alone. Teamwork can be taught by role playing. This format also addresses the problem of student boredom in doing titration after titration, week after week. This teamwork approach is referred to as "cooperative learning" in the educational literature. I t is "defined a s a structured, systematic instructional strategy in which small groups work together to produce a common product." Features include positive interdependence, individual accountability, student interaction, using the teacher as a facilitator, and developing social skills (8).Cooperative learning has as it goals the encouragement of student-faculty contact, encouraging cooperation among students, encouraging active learning, giving prompt feedback, emphasizing time on task, communicating high expectations, and respecting diverse talents and ways of learning (9). Role lav vine h e l ~ to s pive a structured, systematic format for iea&ng teamwork. Course Description The laboratow meets twice weekly for three hours each period and a c ~ o & ~ a n iae slecture that meets twice weekly for 50 minutes. Students receive a single made for four credit .. --hours. ~ --- - ~ The calendar for the lab portion of the course is divided into two sections. The first section (see Table l),lasting but four weeks (one-quarter of the semester), is a n introductory period in which students perform experiments individually in order to gain a quick but sufficient indoctriuation in the skills needed to perform quantitative work:
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weighing, pipetting, reading burets, quantitative transfers. etc. During the first week thev check-in, receive a safety lecture, l e a r n how to use Material safety Data Sheets (MSDS). perform exercises on a n analvtical balance (101, learn buretand pipet use, and receive & introduction to the use of spreadsheets. The next three weeks are spent performing a traditional gravimetric chloride determination, a precipitation titration, and a n acid-base titration. The remaining nine weeks of the semester are devoted to the teamworklrole-playing lab program. Students are divided into teams and each week rotate through a different role in a different experiment in a round-robin format. Each week during the round robin there are a s many difTable 1. Laboratory Schedule Ween 1 Week 2 Week 3 Week 4 Weeks 5-13
. .-
~neck:inieailhand safety ~roceoxes, Baance Glassware an0 Cornp-ler Use Gravimetric Chloride Argentimetric Titration of Chloride by Fajan's Method Determination of Sodium Carbonate by HCi litration Round-Robin Experiments Determination of Calcium by EDTATitration Determination of Copper by Sodium Thiosulfate Titration Determination of pKa and Molecular Weight of an Unknown Organic Acid Determination of Ascoriic Acid in Vitamin C Tablets Atomic Emission Determination of Lithium Ion Exchange Determination of the Formula Weight of an inorganic Salt Spectrophotometric Xtration of Iron by EDTA Gas Chromatographic Determination of an Unknown Mixture Delermtnal on of iron by LV-ViS Speclropnolomelry LS ng 1 ,lo-phenantnroine
ferent experiments being performed as there are teams. Team assignments are made by the professor and are made so as to achieve balance between teams in terms of gender, race, and skill so as to match the diversity that they will one day find in the workplace. The composition of the team is maintained for the entire semester. Role Playing
Role playing is different than working as "lab partners". Definite responsibilities and duties are assigned. No one can be a passive observer allowing someone else to do all the work. Lab questions are included on tests and the final exam, thus providing an additional impetus for each student to know and understand the tasks everyone else is performing. The professor plays two roles as "upper management" and "outside consultant". Even though the professor maintains a constant presence in the lab observing activities, the professor is involved most directly in working with the team manager. In fact, except in emergency cases, the professor will answer questions only from the team manager. Each team has three members: a team manager, a chemist, and an analyst. Each person plays a different role each week, filling each role three times during the rotation. Exchange of roles during an experiment is not allowed. The success of each team depends on the contribution of all team members. Failure to cooperate can lead to the "termination" of a team member and the subsequent assignment of the grade of "F" for the course. Although team members perform different roles, each is responsible for understanding all the chemistry that is involved in the project for that week. All are required to understand the data and results. The team manager furnishes all team members with copies of the final results. The team manager is the person who directly receives the grade for the experiment and the team members receive that same grade. The manager schedules a minimum of two appointments with upper management, one prior to performing the lab and one after the completion of the lab. The first appointment is to discuss the upcoming project, while the second is to report the results. Coming for the report interview the team manager brings a 3.5-in. or 5.25in. diskette with results. Appointments can only be scheduled in person or by phone. The team manager is the person who "knows all the answers" for the team. The chemist and analyst on each team address all their questions to the team manager. In order for the team manager to "know all the answers" the team manager must be well-prepared. The team manager schedules a meeting with upper management prior to the lab period. Prior to this appointment the team manager is to read all preliminary material. Special techniques and equipment are discussed a t this meeting. Sample spreadsheets are discussed in order to give the team manager a preview of how calculations are to be performed. Mock data is provided for the team manager so that the team manager can then create their own template spreadsheets prior to coming to the lab. As data is collected the team manager can then do calculations on the fly. During the lab the team manager is responsible for the team, directing work, giving guidance, and solving problems. The manager is responsible to see that proper safety procedures and good laboratory practice (GLP) are followed. The team manager is to explain to the other team members the proper techniques to be used as well as the operation of any special equipment. The team manager is responsible for development of all necessary software as well as data treatment. The team manager must call a team meeting to discuss the results and have everyone approve of the results.
At the report meeting the team manager brings a floppy disk with all spreadsheets and plots stored on the disk. At the meeting the results are reviewed with upper management and the grade for the project assigned. If necessary, lab notebooks of team members may be brought to justify results. The chemist of each group is responsible for the preparation and certification of standards as well as the setting up of all equipment. GLP and proper safety practices are to be followed a t all times. The chemist is responsible for calculations involving the preparations of standards. The chemist must be able to interpret data to the analyst as well as to the team manager. The analyst for each group prepares each sample and performs the analysis of the sample. The analyst must be able to interpret all data to the team manager. In case of groups that have more than three people, the fourth position will be a second analyst. Due to the division of labor there is ample time within the lab period to hold preliminary discussions with the team as well as to exchange data. It may be necessary to schedule additional meetings outside of the lab period to completely work up the data and to finalize results. Lab work may be performed only during the specified lab period, however. All personnel problems that arise in a team are directed first to the team manager and then to upper management as a last resort. Grading Each team starts each project with a grade of 100. Penalties are assessed for improper techniques or safety practices, for gross negligence, for failure to be prompt, breakdown in team cooperation, and for poor results. Most unknown samples are purchased from Thorn Smith Laboratories (7755Narrow Gauge Road, Beulah, MI 49617). Accuracy is typically grading on a one part-per-thousand relative error basis. Table 2. Average Grade Comparison of Role Playing versus Traditional Method
Experiment Gravimetric Chloride Argentimetric Chloride Soda Ash 'Calcium by EDTA 'Copper 'P16 'Vitamin C 'Atomic Emission 'Fe by VV-VIS 'Gas Chromatography Average over all 10 experiments Standard deviation, all 10 experiments Average over 7 role played experiments Standard deviation , 7 role played exp. Number of students Are the averages significantly different?
Role Playing Lab Section 82.1 79.5 77.5 82.4 70.4 84.4 84.7 84.5 91.7 83.9 82.1 5.6
Traditional Lab Section 81O . 81O . 84.6 75.8 80.9 88.6 82.7 82.8 78.4 82.1 81.8 3.4
83.1
81.6
6.4
4.0
20 19 No (t C ~ I C= 0.538, dof = 6, t m = 0.727)
'denotes mle played experiments Note--each section also performed three additional experiments that were not common to both sections
Volume 71 Number 11 November 1994
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Table 2 compares the mades received during the same semester for one section- that employed the r&-playing approach versus a laboratory section that operated in the traditional method. The two sectlons oetiormed 10 exoenments in common, seven of which the role-playing section performed in the described round-robin sequence. Advantages There are advantages of the role-playing approach besides the learning of how chemistry is done by a teamwork approach. Students feel less pressure from the clock a s the in-lab work has been divided between the chemist and analyst. They are able to confer with their peers in a more relaxed atmosphere. Students learn responsibility in carrying out their duties. As team managers they must exercise oraanizational and managerial skills a s well as teach chemistry and instrutheir t;?am members the ment operation involved with each experiment. The student also performs far fewer titrations than in the traditional laboratory approach due to the division of labor. This reduces the titration-boredom syndrome often encountered a s the semester progresses. For the professor there is a chance to interact with each team manager on a more personalized and individual basis and the discontinuation of having to give a pre-lab lecture each week to a n entire class. I n terms of materials, fewer reagents, fewer unknowns. less elassware. and less instrumentation are required than if aii experimknts were performed individually For example, instead of needing twenty-four pH meters for a full lab section to cany out a pH titration, now onlv one is needed. Waste disposal reauirements are also redked. There is a time savings in regards to lab sebup in that each week there is no need to remove one set of reagents and special equipment from the counter and replace it with another. Once the round-robin begins only replenishment of chemicals needs to be done. When asked to compare how much they learned from performing labs a s teams when compared to a traditional format 47 % of the students responded "more", 32 % responded "about the same", and 21 % responded "less". When asked what they liked best about the role playing method some favorable student comments include: Wurklng in teams rnrnnr > n u lkarned more from your partner. It 1s a better real world srrnnnn than dmng mdmdual lab? It
teaches cooperation. The interaction aided problem solving.
Helps teach leadership when you're the hoss and help[sl ta understand what's going an when working with others. Less oressure. It didn't seem like I had as many tasks and pmuedures to perform. I only had rn he reipons~hlefor accuracy of a few jobs. I.mrnlng rn he a team player and learning toorganiw assignments in a group. Disadvantages There are some disadvantages. For the students their grade is now a function not solely of the individual's efforts but of the team's efforts. A weak team member can pull down the grade of the entire team. Some personality clashes arise a s some students are satisfied to do "C"work
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Journal of Chemical Education
while others are satisfied with nothing less than "A" work. There is the ~ossibilitvthat since the work load is divided into thirds th'at the amount of learning is divided similarly For the omfrssor additional out-of-class time is rrauirrd to meet wi'th each team manager each week. ~ u r i n ~ ' t h first e cvcle through the round robin time must be spent reem;hasizing cow the teamwork approach is to operate and how role-playing is a vital part of the program. As the semester progresses these sessions tend to become shorter as team managers know better what is expected of them. A typical preliminary interview averages 15-20 min while the follow-UDinterview averages 5-10 min. There is more out-of-class time spent by theinstructor meeting with students with the role-playing approach. For a lab section with eight teams this means adds up to about three hours of out-of-class meetings. Some student comments about disadvantages of the role playing work approach included: You did not get to do all aspects in each lab, therefore sometimes I was not aware of what the other members were involved in. Sometimes you don't get to learn all the procedures. Being the boss and having to worry about turning in the lab and the grade [the group1 would then get. Future Directions The round-robin format provides a n opportunity to readilv trv new ex~eriments.In a traditional format where all siud&s perfirm a n experiment a t once there is no chance to fine tune instructions and orocedures and i m ~ l e m e n t these changed until the next $emester. With the roundrobin format such fine tunina can be accom~lishedeach week before the next group p&forms that experiment. Innovative problems can be introduced such as mock forensic analyses ill).An idealway to conclude the semester would be to have as a capstone experience a method development experiment (12). I n the future it is hoped to try out new experiments such a s these for incorporation into the course. Acknowledgement The author wishes to thank Garv L. Asleson and W. Frank Kinard for their comments aAd suggestions in developing this program. Copies of round-robin schedules, sample data, 1-2-3template worksheets, handouts, and report interview forms are available upon recluest from the author. Literature Cited 1. Vorress. L. Anal. Chom. 1991.63.347A. walters; J. PAnd. Chem. 1991,&,977A. 3. Waiters, J. PAnol. Chem. 1991,63.1017A. 4. Wa1tem.J. PAnol. Chem 1991,63.1179A. 5. Quigley M . N. InfemofiomINewsl.chom. Edue 1991.35.4. 6. Day. R. A ; Underwood,A. L. Quonflfaliw Analysis, 6th ed.: Rentice Hall: Enele-
2.
&a c~iw.NJ,1991. 7. Goofnick. D. E.; Gwmick, M. M., Today> Chemist at Work 1992.1 161.38. S. Cooper, J.The %ch. Pmf 1990.4 151, 1. 9. Millis, B. J. J Ercdl. CoNTeoch. 1991.2, 139. 10. Richardson,TH. J. Chem. Edue 1991.68.311.
11. Mureia,N.S.;Lundquist,E.G.:Russo,S.O.:Petera,D.G. J.Chom.Educ 1990.67, ROP
12. Campbell, D. L. J Chem. Educ 1991.68.184
