John A. Buono and James 1. Farching University of Rhode Island Kingston, 02881
I
Initiative, Ingenuity, Creativity, and Chemistry, TOO? A group approach to analytical projects
Undergraduate chemical laboratories have mainly consisted of prepared and tested conventional lab experiments which guide a student to a desired result. A second class of laboratory experiments revolving around projects or independent study have been gaining in popularity in recent years (1, 2). Wehry (3)has developed "open-ended" experiments in analytical chemistry which are small relevant problems that a student can solve in the last six weeks of a semester. The Analytical Chemistry Department a t the University of Massachusetts (4) has developed a similar program encompassing all laboratories in their analytical chemistry division. A program consisting of individual conventional lab experiments and group special projects during the last 6-8 weeks of a semester has been associated with lectures in undergraduate analytical courses a t the University of Rhode Island (URI) since 1970. One of the drawbacks of "open-ended" or special projects for students is the fact that it is hard to find a lab prohlem that has the following criteria: (1) that it is a real (relevant) problem in chemistry, (2) that the scope of the problem be broad enough to allow the student a variety of ways of finding a quantitative solution, and (3) that the lab problem must be of such length and simplicity that the student can solve the problem in 6-8 weeks. The special projects that were developed a t URI are based on group efforts, allowing much more complex problems to be undertaken in the laboratory, thus the students get experience working in a group and under a group leader. They select their own problems, develop procedures for solving these analytical problems, apply these procedures in the laboratory to glean experimental results, and compose a final report. All this provides a basis for an evaluation of a student's initiative, ingenuity, and creativity. Description of Laboratory Courses
After one half of a semester of conventional laboratory experiments in quantitative analysis (5,6) and in instrumental analysis (71,students are introduced to a somewhat unconventional array of special projects (see Tahle 1). Tahle 1 is a list of the projects completed by URI students. Some of these project topics were studied by more than one group, each using a different approach (e.g., lead in gasoline by spectrophotometric analysis, gravimetric analysis, or atomic absorption spectrometry). Students are placed into project groups specifically arranged by the laboratory instructor and the lecture instructor. These groups are organized to have an above average student as a group leader, one or two average students and a below average student hased on averages from the - generated . convekional laboratory experiments. Once a group is formed, it is instructed to select any project that would requirequantitative analysis. If the boup~doesnot generate its own problem, then it selects one from a list of suggestions (see Table 1). The group, with a potential project, then spends a laboratory $eriod in the library searching for two independent methods of performing their particular analysis. The group receives no help from 616 / Journal of Chemical Education
Table 1. Suggested Group Projects
Determination of Phmphate in Detergents. Determination of Phosphate in Natural Waters. Amino Acid Separation and Determination. Determination of Citric Acid in Fruit Juices. Determination of Buffering Capacity of Antacids. Determination of Various Ions in Natural and T a p Water. Determination of Percent Ethanol in Beer. Determination of Percent Ethanol in Whiskey. Determination of Dissolved Oxygen in Sea Water. Determination of Percent Ethanol in Urine. Comparison of Volumetric Analysis versus Gravimetric Analy"'
SLS.
Analysis of Tea. Determination of Lead in Gasoline. Determination of Zinc, Calcium, Iron in Blood. Determination of Creatinine in Blood. Analysis of Cumberlandite. Assay of Pharmaceuticals. (a) Terpin Hydrate (b) Vitamin Pills (c) Chlorothiazide 18. Determination of Lead in Dinnerware and Pottery. 19. Determination of Iron in Blood (effects of iron pills) 20. Determination of Drugs in Urine.
-.- .......
25. Determination of CODD&. Mercury. and Chromium in River , ,,
.
26. A*,ay uf"Speclal K" Brcakfaqr Cereal for Prorrin. Far, rrc 27. l)ererm:?at:on of Caffe~ne. Acrdtry. Preierratl\,e\ ~n Carbonated Beverages. 28. Determination of Cholesterol Level of Blood versus Cholesterol
....
"
29. Ikrerminatim of Ethanol. Aldehvdea and Carbc hydrate. During I.'ermenrationafC.rape.lu~ce. 30 Dcrerminnrion of Aridity of Coffee.
the instructor until this literature search is complete. The group then consults with the instructor concerning the feasibility of the methods of analysis they have chosen, the availability of equipment, chemicals, and the time required to complete the project. Once a project has been cleared bv the instructor. it is UD to the mouu to show initiative and ingenuity to solve theanalytical prbblems. The role of the laboratory instructor is to troublesh&t problems and to advise groups as they progress with their projects. The instructor must he constantly aware of the difference between a group's valid need for help on project problems and a group's unwarranted dependency on the instructor for the solution of its prohlem. The responsihility for the actual completion of the project lies on the group leader. He functions as a "supervisor," coordinating and establishing a general work program to he followed by the group. Once the project has been completed a 10-100 page typewritten report is submitted to the instructor. In some cases, student evaluations of each other are solicited because the group developed personal difficulties which interfered with its program of analysis. These evaluations aid the instructor in the task of grading the lahoratory.
Project Evaluation and Laboratory Grading Scheme The written report for each special project is graded on the basis of the following four categories E represents the degree of difficultyof the project. 0 represents the originality and ingenuity of the students with respect to the completionof their project. S represents the extent of the students' scientific approach to the project. R represents the evaluation of the written report on the project with respect to scientific merit, conclusions, explanation of discrepancies between theory and experiment, and the group's ability to communicate the project results on paper to the instructor.
The relative grade weights of these four categories are 30, 40,40,40, respectively. Each report is graded independently by two to four instructors and the results of these separate evaluations are averaged as a means of increasing the objectivity of the grade. In addition to the grade based on the written renort. each student also receives a made (up to 150 pdintsj for his overall performance in the group effort and his contribution to the success (or failure) of the project. These grades are also averaged and adjusted if necessary to take into consideration the group leader's and the student's own evaluations. The student's final project mark is based upon the above two grades which have been computed as objectively as possible. A few poor students show no initiative or incentive under either teaching approach. Similarly a few superior students show the same enthusiasm, initiative, and creativity under both approaches. However, the group apnroach allows the in&uctor to eain a fresh evaluation of the vast majority of students who lie between these two extremes. Experience has shown that one cannot say which calibre student (i.e., superior, average, poor) will think up the project or even which student will be the driving force in the group. Although the groups are selected to he of equal capabilities (on the basis of the conventional laboratory experiments), one rapidly discovers that conventional lahoratory experiments do not adequately show a student's full potential. It is quite common to find an average student working as hard as or harder than a superior student and producing better results. The undertaking of a group project has a varied effect on most of the students who participate in this technique. A few students who performed poorly on conventional laboratory experiments also performed poorly on the group project. While it may be argued that these students possibly receive an undeserved increase in their grade due to the efforts of their coworkers, these students for the most part receive characteristically low instructor and peer vroiect evaluations which account for 50% of their . - made. Conversely, a few superior students might suffer from a lower project mark as a result of being graded with the group. If this detrimental effect is undeserved, it will be offset by an increase in the superior student's individual evaluation grade. Thus while the concept of grading students in groups could possibly produce a leveling effect on mades in wneral. i t is the authors' intent to offset this efTect by the-individual evaluation grade. A random samvle of the mades of 20 out of 114 quantiin Table 2. T W ~avertative analysis &dents is ages for each student are tabulated. Column I contains the averages based on conventional laboratory experiments, column II contains project grades, and column is the difference between project grades and conventional laboratory experiments. A difference of ten points or more of at least a letter grade between the two is a types of laboratory exercises. Out of the 114 students in laboratory course' 53 had a change Of greater than lo percentage points. If conventional laboratory experiments achieved the academic goals postulated, then one would
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Table 2. Laboratory Grades of Twenty Students
Student
I Conventional I1 Laboratorv (7%) Proiect (7%)
11 57 71 12 52 24 113 29 46 17
20 46 73 53 71 51 69 61 60 56
78 58 68 59 59 55 57 73 60 82
1nR
RR
75
30 96 25 64 67 66 43 95 76
71 51 77 63 74 53 74 68 48
51 63 76 53 57 68 82 48 58
-*-
--
.-
Ills
Difference (7%) L+W [+l;l +6 (-12) +4 (-12) [+I21 0 [+26l
,1+171 .
(-14; [+I;] (-10) (-17)
[+;I
(-20) [+lo1
[ 1; Indicates an increase of at least a letter grade in f i n d average; ( ): Indicates a decrease of at least a letter grade in final average. predict that the student's performance levels on the !wo different lahoratory approaches would be the same. Table 2 shows that for approximately 50% of the students the above prediction is not valid. Twenty-eight students who did poorly in the first part of the course excelled during the special projects portion. Also, the reverse is true, 25 students markedly dropped in performance.
Conclusion Special projects and conventional experiments promote and test different aspects of a student's capability. Conventional experiments test a student's ability to follow established procedures while special projects test a student's initiative, ingenuity, creativity, scientific curiosity, and ability to work with others. These are traits which a student will find useful in a scientific career but which are not usually developed or tested in a conventional laboratory scheme. Conventional laboratory experiments force a student into a rigidly timed program while conversely, special projects teach the student the much needed virtue of self-discipline. The undertaking of special projects gives a student a real understanding of how science is applied to problems in today's world. The authors are not advocating that special problem experiments replace conventional laboratory experiments; however, when used in conjunction with classical laboratory experiments, special projects greatly enhance the educational aspects of analytical chemistry laboratory courses. Acknowledgment Valuable assistance in instructing the various laboratories was contributed by G, J, ~ i l b M. ~ W. ~ ,prechette, R, W, Karin, p. R, Walsh, and J , p, M ~ ~h~ ~authors ~ wish to thank ~i~~ D. L. Littmann for reading the manuscript and for suggestingimprovements, Literature Cited (1) Miilcr,J.M.,J.CHEM.EDUC.,SO.185(1973). (2) De Rae, J. V., J. CHEM EDUC..47,553 11970). (3, Wehry,E.L., CHEM. E ~ ~ c47,84311970). . , (41 ~ d i t . l~~ n~ a~~ y, t ichemistry ~si at the university of ~absschusetts."~ m f chem., . 41 No. 12, 27A(19691. (5) Fiseher, R. B., and Petera, D. G.,..Quantitative Chemical Analysis? (3rd Ed.), W. B. s a ~ d e mcompany, west w-hingtm square. phiisdeiphia, pa., IBIOS.1968, pp. 195,312, 395. 439aodM1. (6) Skwg, D. A,, and Wept. 0. M.. '"Fundamentsls of Analytical Cherniatri," (2nd ~ d . ) H&. . ~ i ~ e h s and r t winston, h c . , NW york, NW york, 1969, ~ p 232, . 309. 331.342 and689. (7) Willard, H. H..Memitt, Jr., L. L.,and Dean, J. A., %sirurncntal Methods af ~ ~ s l ~ a i (4th s , " ~ d . 1 v. . van ~ o e t r a n dcompany, h., ~ l i n c e f o n ,N ~ W~ e n e y , 1965, pp 32. 74.120, 309, 494, 64~,660,6'12,7n3and713.
Volume 50, Number 9, September 1973 / 617
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