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Enhancing Undergraduate Education Curriculum Modification and Instrumentation Dennis G. McMinn, Kay L. Nakamaye, and Joanne A. ~ m i e j a ' Gonzaga University, Spokane, WA99258
Three years ago, the Chemistry Department of Gonzaga University implemented a significant modification of the traditional curriculum for science majors. The department consists of five full-time chemistry faculty and one biochemistry faculty shared with biology. The goals of the modification were threefold: (1) to make lower division courses more accessible to a
broader student population; (2) to make the lecture and laboratory material more consis-
tent with what chemists actually do; and
(3) to prepare chemistry majors far independent research.
The plan that emerged included starting organic chemistry in the freshman year, incorporating a new descriptive inorganic chemistry course in the sophomore year and, for chemistry majors, replacing upper division discipline-specific lahoratories with a unified laboratorv seauence. Table 1.I n the lower division lahoratories, discovery-based exercises have been added and the use of instrumentation increased. Students are introduced to modern instrumentation in the beginning courses and perform increasingly sophisticated experiments a s they progress through the curriculum. This DaDer describes the new curriculum and why it is a n attrackGe alternative for training undergraduates. "
A
The New Curriculum The new cumculurn begins with one semester of general chemistry. I n the fall of 1993,250 students enrolled in this course. After much discussion, the faculty chose the topics listed in Table 2, because they are fundamental in chemistry and are essential to prepare students for the next
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This paper was presented at the 207th American Chemical Society National Meeting in San Diego, CA, March 17, 1994.
course in the curriculum, organic chemistry. The emphasis in the general chemistry course is qualitative not quantitative. For example, when discussing equilibrium, Le Chstelier's Principle is stressed, not equilibrium calculations. Topics listed in Table 2 a s introductions are only briefly discussed. In the general chemistry laboratory, two sections are comprised of chemistry majors and students with strong chemistry backgrounds. The exercises in these sections are discovery based. The students perform experiments to identify trends or properties and then attempt to make conclusions with minimal coaching from the professor or teaching - assistant. A two-semester organic chemistry course follows general chemistry and begins in the spring, Table 1. I t is a traditional organic chemistry course with expanded discussions in areas-that are not ;ntroduct!d tho;oughly in general chem~stry.For example, kineticd is introduced and covered when uni- and bimolecular nucleophilic substitution reactions are discussed. A si~mificantchange is made in the laboratom. however. where IR and NMH soertroscoov are introducld early i n the semester to cooriinate wiig the discussions of structure. isomerism. and functional erouos in lecture. This early introduction i$ reinforced throughout the course in the laboratorv. the lecture.. ~ .r o b l e massimments, and the recitation &tion. The discussion of spectroscopy is more appropriate in the laboratory, where it actually is used and allows a more modest pace in the classroom for the first semester than in a traditional organic course. The spectroscopic emphasis is continued in the laboratory as synthetic techniques, and mechanistic principles are studied and culminate in the identification of a general unknown. Students are organized into groups for t h e general organic unknown and perform initial chemical characterization tests t h a t are, in turn, confirmed or adjusted with IR and NMR spectroscopic infor-
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Table 1. Old and New Curriculum for BS Chemistry Students Old Curriculum Fall
Spring
Freshman
General Chemistry I and Laboratory
General Chemistry I I and Laboratory
Sophomore
Organic Chemistry I QuantitativeAnalysis and Laboratory
Organic Chemistry II Organic Laboratory I
Junior
Physical Chemistry I Organic Laboratory II
Phys ca Cnem srry I and Laboratory lnorgan c Chem~slryOR Upper Division Elective Chemistry Bibliography
Senior
Instrumental Analysis and Laboratory Biochemistry I Senior SeminarIResearch
Inorganic Chemistry OR Upper Division Elective Senior SeminarIResearch New Curriculuma
Fall
Spring
Freshman
General Chemistry I and Laboratory
Organic Chemistry i and Laboratory
Sopnomore
OrganIc ChemIsKy N and Lamratoly Inorganic Chemrstry and Laboratory
QuantitativeAnalysis and and Laboratory
Junior
Physical Chemistry I Unified Laboratory I
Physical Chemistry II Unified Laborafory N inorganic Chemistry OR Upper Division Elective Chemistry Bibliography
Senior
Instrumental Analysis and Unified Laboratories 111 Biochemistry I Senior SeminarIResearch
lnorganrc Chemrsfry OR Upper DIVston E eclive Sen or Sem nar Researcn
'Changes in Italics
mation. After final chemical characterization, the students utilize GC-MS to confirm the identity of the unknown. A new soohomore-level inorwnic chemistrv course and lab has be& added to the ~ ~ c u l u Table m , i. The topics, Table 3, include some normally discussed in a traditional second-semester general chemistry course-thermodynamics, acid-base equilibria, solubility products, solids, electrochemistry,nuclear chemistry, and coordination compounds. In addition, the course includes a significant amount of descriptive inorganic chemistry with an emphasis on periodic trends and environmental chemistry. Although-the new course is qualitative in nature, it does require students to perform mathematical exercises, such as equilibrium calculations. The lab for this new course includes discovery-based exercises to explore periodic trends, determine equilibrium constants, and qualitatively analyze unknown aqueous solutions. With the addition of the new sopbomore-level course, the upper division inorganic chemistry course was modified. Because the sophomore course includes discussions of descriptive inorganic chemist^. oxoacids. redox chemistrv. andsolids, less time is neededin the upper division cour;; for these topics. In the revised curriculum, the upper division course~concentrateson more advanced topigsuch as group theory, molecular orbital theory, bonding and spectroscopy of transition metal complexes, organometallic chemistry, catalysis, and bioinorganic chemistry The upper division labs also have been revised. In the old cumcuiu-m, there were three semesters of discipline-specific lahs. The first emphasized organic synthesis and technlques, the second physical methods, and the third instrumental analysis. The new curriculum contains a three-semester unified lab sequence (1).The first semester
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Journal of Chemical Education
in the sequence meets six hours a week; the second, eight hours a week; and the third, four hours a week. The students are assigned projects that typically require several laboratory periods to complete. Most of the projects are based on articles from this Journal (see Table 4 for recent examples) and involve a combination of synthesis, physical characterization, and spectroscopic characterization. The goal in these experiments is to complete the students'acauaintance with a wide varietv of instruments. technioues., and principles. The experiments are designed to move students toward independence and facilitate the type of thought and analysis required in a research setting. The remainder of the cumculum is unaffected. Aauantitative analysis course is offered in the sophomore y e k and continues to he a lahoratorv intensive course. Advanced course offerings complete the ACS-approved curriculum, includine those reauired for the hiochemistrv . option. Chemistry majors are required to complete a research project. A chemical bihlioaa~hvcourse is offered everv s ~ r i n e "to introduce juniors tz the iiterature and to help "them t i choose a reasonable senior project. Students are expected to perform their research during their senior year. Tb graduate, students are required to present their results to the department in a departmental seminar, as well as to submit an acceptable written thesis.
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Discussion The curriculum modification has been beneficial in several ways. (1) Many students a t Gonzaga University are interested in health-related or environmental careers. Thus, organic chemistry is more relevant than are the topics discussed in a traditional second-semester general chemistry course.
Table 2. Topics Discussed In General Chemistry 1. Atomic Structure a. Nucleus b. Electronic Structure c. Periodic Trends 2. Reaction Stoichiometry a. Balancing Equations b. Limiting Reactants c. Theoretical Meld 3. Gas Phase Reactions a. Ideal Gas Law b. Introduction to Kinetic Theory of Gases 4. Reactions in Solution a. Molar Concentration b. Precipitation Reactions c. Arrhenius and Bronsted-LowryAcid-Base Reactions d. lntroduction to Redox Reactions 5. lntroduction to lonic Bonds a. Nomenclature of lonic compounds b. Periodic Trends in Bonding 6. Covalent Bonds a. Nomenclature of Molecules b. Lewis Structures c. VSEPR Theory d. Polar and Nonpolar Molecules e. Intermolecular Forces between Molecules 7. Thermochemistry a. lntroduction to Calorimetry Experiments b. Exothermic and Endothermic Reactions C. Enthalpies of Formation 8. lntroduction to Equilibrium a. Le Chatelier's Principle b. Definition of Equilibrium Constant c. Definition of Ka, Kb, and pH
Placement o f organic chemistry int h e freshman year helps r e t a i n student interest during t h e crucial f i r s t year. The a d d i t i o n o f t h e sophomore-level i n o r g a n i c c h e m i s t r y course e m p h a s i z i n g e n v i r o n m e n t a l c h e m i s t r y also i n creases t h e relevancy o f t h e p r o g r a m for t h e students. In addition t o s e n i n g t h e needs of chemistry majors with a n environmental interest, t h i s course also fulfills one of t h e requirements for students completing Gonzaga's c i v i l engineer program w i t h a n environmental emphasis t h a t was i m p l e m e n t e d concurrent w i t h t h i s c u r r i c u l u m modification. Several c i v i l engineering students h a v e opted t o complete a chemistry minor. ( 2 ) Placement of organic chemistry in t h e freshman year also promotes analytical t h i n k i n g e a r l y in t h e student's chemistry education. A s stated b y Doyle (41,
There i s a wealth of organized knowledge about chemistry in the introdudarv " orpanic chernistrv course. and the beautv of i t s expression lies in the integration of principles and thei;applications, of structure, dynamics, and synthesis. No other subdiscidine of chemistry possesses the uniformity of content that ehar&erizes the first Eourse in organic chemistry Also, t h i s early emphasis o n organic chemistry coordinates better with t h e biology c u r r i c u l u m as it becomes increasingly m o r e molecular in nature. To obtain a B S in biology, Gonzaga students a r e r e q u i r e d t o complete f o u r semesters o f chemistry: one semester of general chemistry, t w o semesters of organic chemistry, a n d either t h e quanti-
Table 3. Topics Discussed In N e w Sophomore Inorganic Course 1. Thermodynamics a. Review Reaction Enthalpy b. Entropy of Reaction c. Free Energy and Spontaneous Reactions 2. Periodic Trends a. Review Trends in Ionization Energy, Electron Affinity, and Electronegativity 3.Acid-Base Properties of Metal Cations and Oxoanions a. Review Acid-Base Definitions, pK, and pH b. Trends in Metal Cation Acidities c. Nomenclature and Basicities of Oxoanions 4. lonic Solids a. Lanice Types b. Radius Ratio c. Lanice Energy 5. Precipitation Reactions a. Thermodynamics of Precipitation b. IGpand IGpCalculations c. Solubility Rules 6. Oxldation-Reduction Chemistry a. ElectrochemicalCells b. Cell Potential c. Nernst Equation d. Redox Trends e. Pourbaix Diagrams 7. Elemental Properties a. Nuclear Stability b. Physical Properlies of the Elements 8. lntroduction to Coordination Compounds a. Review Lewis Acid-Base Definition b. Classification of Ligands c. Hard and Soft Acid-Base Principle
Table 4. Examples of Unified L a b Experiments
1. Polymerization and Co-polymerization of Styrene: Kinetics and Characterization (2) a. Techniques Used - Synthesis, Computer Analysis of Kinetic Data, and Molecular Weight Measurements b. Instruments Used -Gel Permeation HPLC, FTlR Spectrophotometer, 'H NMR Spectrometer, UV-Visible Spectrophotometer,and DifferentialScanning Calorimeter 2. Preparation and Characterization of an Iron Porphyrin Complex (3)
a. Techniques Used - Synthesis, Thin Layer Chromatography, and Evan's Method to Determine Magnetic Susceptibility b. Instruments Used - Cyclic Voltammograph, UV-Visible Spectrophotometer, FTlR Spectrophotometer, and 'H NMR Spectrometer tative analvsis course or t h e s o ~ h o m o r einorganic chemis-
try course.
(3)M a n y incoming first-year students have modest m a t h skills. T h e n e w c u r r i c u l u m postpones mathematical data analyses until t h e sophomore year. T h i s provides t h e students a n opportunity to improve t h e i r skills before they are r e q u i r e d t o do significant q u a n t i t a t i v e analyses in t h e i r chemistry courses. ( 4 ) In keeping w i t h t h e desire t o show a l l science students w h a t chemists actually do a n d t o prepare chemistry majors for independent research, t h e n e w curriculum possesses more realistic laboratory experiences t h a n did t h e Volume 71
Number 9
September 1994
757
old cumculum. In the lower division courses, the inclusion of discovery-based exercises illustrate the scientific process more accurately than do verification exercises. The synthetic skills developed in the organic chemistry laboratories allow earlier introduction to research. Incorporation of experiments using modern instrumentation, as early as the freshman year, conveys to the student an accurate description of how today's chemist operates. As students progress through the curriculum they perform increasingly more sophisticated experiments using the same instrumentation. In the upper division unified lab courses, the projects require several lab periods to complete and are cross-disciplinary in nature. Aunified lab project may require a synthesis, spectroscopic characterization, and analysis using a physical method. The goal is to prepare the chemistry major for the senior research project and graduate school or a career as a scientist. (5) A final beneficial outcome of this curriculum modification is increased communication among the faculty. Prior to initiating the changes, the faculty discussed what each believed was important in an undergraduate education. As the modification was implemented, discussions were continued to ensure that all important principles are included in the cumculum. These discussions have increased our understanding of what is taught in each course and have resulted in a stronger, more coherent program. Two difficulties were anticipated with the new curriculum. First, the new cuniculum was expected to be problematic for students interested in a Bachelor of Science in chemistry who transferred from a traditional program into Gonzaga University their sophomore year. If these students had a year of general chemistry, they would be eligible to enroll in the sophomore inorganic chemistry course, but they could not begin the organic chemistry sequence until the spring semester of their sophomore year. This would make it difficult for them to complete all the chemistry requirements in four years. This problem is mitigated to some extent if the transfer student chooses the biochemistry option of our BS degree. A second concern with the new cumculum is the time between the first and second semesters of the organic chemistry course. In a traditional program, the break between the two semesters is usually less than a month. With the new curriculum, three months elapse between semesters. As suggested by Mike Doyle (5).setting aside four to six lectures a t the beginning of the course where significant time is spent in review alleviates student anxiety and accomplishes a smooth transition. Indeed, the summer break has not been a problem. Some students have re-
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Journal of Chemical Education
marked that the summer break served them well, allowing them to relax a little more than they might otherwise have done. Conclusion The new curriculum has been in dace for three vears. Formal evaluation has been difficuit because, like &any other institutions. Gonzaga Universitv has ex~erienced sigmiicant increasks in thenumber of students ;aking beginning science courses. No chance in the Dercentaees of &ude&s who complete organic ihemistry'has been observed, which is evidence that freshman can perform well in organic chemistry. Also, there is ample evidence that the junior biology and chemistry maiors who are products of the new cu&iculum are prepared better to handle independent work than were their predecessors. Faculty directing student research note the excellent preparation students have, particularly in selecting appropriate instrumentation for analysis in their research. Anecdotal evidence that the program seems to be achieving the intended goals comes from two new faculty members who were added to the chemistry department this academic year. Both previously taught in programs with graduate students. Both have commented on how well prepared our majors appear to he to pursue graduate-level research programs. In fact, one of these individuals further promoted the proiect-based integrated laboratom bv encouraeine students to design additional experiments to test G e i tions that arose during the assigned experiments. This is the type of activity we hoped our students would be able to do when we initiated these cumcular than-s. After three years with the modified curriculum, we recommend it as an attractive alternative to training quality undergraduates. Acknowledgment The authors would like to thank the National Science Foundation Instrumentation and Laboratory Improvement Program for partial funding of the thermal and electrochemistry equipment (DUE-93507881, the GC-MS (DUE-9351183), the NMR spectrometer (USE-9152468), and the biochemistry equipment (USE-9151396). Literature Cited 1. Cartmight, J. M. J Chem. Educ lSW, 57,30%3ll.Gaadney, D. E.: Hudak, N. J.: Chapple, E H.; B d ,C. P.J Chem. Edue 198%. 61,703-706. 2. Hardgmve, G. L.;T m ,D. A; Miessler, G. L. 3. Chem. Educ. 1890,67,979--981. 3. Geiger, D. K J. Ckem Educ 1991.68, 34G.342. 4.Doyle, M. P. Council on undp,gmdun&ResoomkN~~~h*r IS%,, 10, 3M7. 5. Doyle. M. P. Personal mmm""kation.
