Selected Papers from Regional Conferences 1966-67 Selected Papers from Regional Conferences 1966-67

REPORT RESUMES SE 004 913 ED 020 915 SELECTED PAPERS FROMREGIONAL CONFERENCES2966-67. BY- MARQUARDT, D.N. ADVISORY COUNCIL ONCOLL. CHEMISTRY PUB DATE MAY 68 REPORT NUMBER AC3-PUB440-35 EDRS PRICE MF-40.50 HC -$3.36 82P. SCIENCE, DESCRIPTORS- *CURRICULUMDEVELOPMENT, *COLLEGE STUDY, *CHEMISTRY, *COMMUNITYCOLLEGES, *UNDERGRADUATE CONFERENCES, INSTRUCTION,LABORATORY SAFETY, ORGANIC TECHNIQUES, ADVISORY CHEMISTRY, SCIENCEACTIVITIES, TEACHING COUNCIL ON COLLEGECHEMISTRY,

REPORTED ARE 15 SELECTEDPAPERS ON VARIOUSTOPICS OF CURRENT INTEREST WHICHWERE PRESENTED ATTHE VARIOUS REGIONAL CONFERENCES CURING 1966AND 1967. THE VARIOUSCONFERENCES TRENDS IN GENERAL HAVE AS THEIR MAJORCONCERNS (1) RECENT (3) TEACHING CHEMISTRY,(2) CHEMISTRY FORGENERAL EDUCATION, UNDERGRADUATE ORGANICLABORATORIES, (4) THEINTEGRATED (6) LABORATORY,(5) THE GENERALCHEMISTRY LABORATORY, CHEMISTRY, AND CONTEMPORARY DEVELOPMENTIN TEACHING GENERAL PAPERS ON THE (7) NEW APPROACHES TOLABORATORY INSTRUCTION. FOLLOWING TOPICS AREINCLUDED IN THISPUBLICATION(1) CHEMISTRY COURSE, TEACHING CHEMICAL BONDING,(2) THE GENERAL LABORATORY, (3) INSTRUCTIONALTECHNIQUES, (4) INTRODUCTORY (6) THE GENERAL (5) CORE CURRICULUMLABORATORY PROGRAMS, LABORATORY, (8) CHEMISTRY LABORATORY,(7) THE INTEGRATED STRUCTURED CHEMICALEXPERIENCES, (9) DEMONSTRATION EXPERIMENTS, (10) COMPUTERSIMULATION OF LABORATORY INTRODUCTION TO ORGANIC INSTRUCTION,(11) ANALYTICAL CHEMISTRY, (12) LABORATORYSAFETY, (13) TEACHINGNON-SCIENCE COLLEGES. (DH) MAJORS, AND (14)CHEMISTRY FOR TWO-YEAR U.S. DEPARTMENT OF HEALTH, EDUCATION &WELFARE OFFICE OF EDUCATION

THIS DOCUMENT HAS BEEN REPRODUCED EXACTLYAS RECEIVED FROM THE

PERSON OR ORGANIZATION ORIGINATING IT.POINTS OF VIEW OR OPINIONS

STATED DO NOT NECESSARILY REPRESENT OFFICIALOFFICE OF EDUCATION POSITION OR POLICY.

SELECTED PAPERS FROM REGIONAL CONFERENCES 1966-67 SELECTED PAPERS FROM REGIONAL CONFERENCES 1966-67

Reports From REGIONAL CONFERENCES Sponsored By The ADVISORY COUNCIL ON COLLEGE CHEMISTRY

-Edited by D. N. Marquardt University of Omaha Staff Associate 1968 Advisory Council on College Chemistry

AC3 Serial Publication No.. .35 May 1968.

11111111111111sornowar RECEIVED

JUL 51968

TILE OHIO STATE UNIVERSITY CENTER FOFt SCIENCE AND MATHEMATICS EDUCATION Advisory Council on CollegeChemistry

Department of Chemistry, Stanford University, Stanford,California 94305

The Advisory Council on College Chemistry, anindependent group of chemists, has as its goal the improvement of undergraduatechemistry curricula and instruction. TheCouncil collects and disseminates information through the activitiesof standing committees on Freshman Chemistry, Curriculum and Advanced Courses, Teaching Aids,Teacher Development, Science for Non-Science Majors, Two,Year College, and Resource Papers.Additional ad hoc groups act as necessary to further assist theCouncil in providing leadership and stimulus for imaginative projects on the part of individual chemists. The Council is one of a group of collegiate commissionssupported by grants from the National Science Foundation.

OFFICERS AND STAFF L. C. King, Chairman *W. H. Eberhardt, Vice-Chairman *C. M. Barrow, Executive Director D. N. Marquardt, Associate '68 University of Omaha Rod O'Connor, Associate '67-'68 University of Arizona

COUNCIL MEMBERS "Cordon M. Barrow '68, Stanford University Edwin M. Larsen '68, University of Wisconsin 0. Theodor Bcnfey '68, EarlhumCollege Howard V. Malmstadt '69, University of Illinois Henry A Bent '69, University of Minnesota William T. Mooney, Jr. '69, El Camino College Francis T. Bonner '70, SUNY at Stony Brook Leon 0. Morgan '70, University of Texas Robert C. Brasted '69, University of Minnesota Melvin S. Newman '68, The Ohio State University J. Arthur Campbell '68, Harvey MuddCollege Milton Orchin '70, University of Cincinnati "W. B. Cook '69, Colorado State University Robert W. Parry '70, University of Michigan Charles F. Curtiss '70, University of Wisconsin Arden L. Pratt '70, SUNY at Albany "William H. Eberhardt '69, Georgia Institute ofTechnology Charles C. Price '69, University of Pennsylvania Technology Richard W. Ramette '70, Carleton College Harry B. Gray '69, California institute of Carolina David N. Hume '69, Massachusetts Institute ofTechnology Charles N. Reilley '68, University of North Emil T. Kaiser '69, The University of Chicago Douglas A. Skoog '70, Stanford University Michael Kasha '69, Florida State University Robert I .Walter '69, Haverford College "L. Carroll King '69, Northwestern University *Peter E. Yankwich '68, University of Illinois Jay A. Young '68, King's College *Executive Committee.

This report is issued as one ofseveral types of publications distributed by the Council.A complete list of all publications is available on request.If you would like to receive the publicationsregularly, send your nameand address to: Publications Office VP' Advisory Council on CollegeChemistry 701 Welch Road, Suite 1124 Palo Alto, California 94304

Please notify us immediately of anychange of address

*04.61100. a... 4.4 PREFACE

In the past year, seven Regional Conferences have beensponsored by the Advisory Council on College Chemistry.Formal presentations by principal speakers, along with question and answer periods and discussion sessions, are animportant part of these conferences. These presentations aredistributed as part of the conference report to each of the participants atthe conference. The availability of these reports to non-participants is announced through theNewsletter.

A few of the papers on various topics of current interest arepresented in this publication so that a wider audience may have an opportunity to see some of the material discussed at AC3 regional conferences.(Full reports of individual conferences are still available on request).

The Regional Conference program is a continuing Advisory Councilactivity and selected material, such as presented here, will be collected periodically. Asthe attached material shows, a variety of topics can be dealt with.(Perhaps even more important than the rather formal presentations reprinted here is theinvolvement of the participants during and following the conference which cannot bedemonstrated in a report such as this.)

We are indebted to the contributors for permission to publish their papers. They were originally intended only for rather informal presentations atRegional Conferences. They are reprinted here in their original style.

The Advisory Council-sponsored Regional Conferences stem from the invitation of an institution to host a conference. We welcome such invitations. Table of Contents "Teaching Chemical Bondingto Freshmen" - Harry B. Gray, Calif. Institute of Technology .1 (from Regional ConferenceNo. 1)

"The General ChemistryCourse: Some Pressures, Problemsand Tentative Solutions" - Robert I. Walter, Haverford College .7 (from Regional ConferenceNo. 6)

"Application of a Response System,Tape-Recorded Material,and Other Novel Techniques in University Chemistry Instruction" 10 - Brian D . Pate, Simon Fraser University (from Regional ConferenceNo. 7) "The Introductory Laboratory- Ideality vs. Reality" and "The Introductory Chemistry Laboratory" .12 - Richard J. Kokes, The Johns Hopkins University 15 (from Regional ConferenceNo. 4 & No. 6) "Plans for a Core Curriculum Laboratory Program" .19 - Gilbert P. Haight, Jr., University of Illinois (from Regional ConferenceNo. 4)

"General Chemistry Laboratory:An Experimental Approach" . 26 - Jerry A. Bell,*University of California at Riverside (from Regional ConferenceNo. 5) "The Integrated Laboratory" .29 - Harry B. Gray; California Institute of Technology (from Regional ConferenceNo. 4)

"Structured Chemical Experience in UndergraduateLaboratories" .35 - John E. Baldwin, The University of Illinois (from Regional Conference No. 3)

"Demonstration Experiments for the ModernGeneral Chemistry Course" .43 - Robert C. Plumb, Worcester Polytechnic Institute (from Regional Conference No. 5)

"Computer Simulation of Laboratory Instruction" .46 - J. J. Lagowski, The University of Texas at Austin (from Regional Conference No. 7)

"An Analytical Introduction to OrganicChemistry "... 48 - Rod O'Connor, Kent State University (AC3) (from Regional Conference No. 3) "Safety in the Laboratory" .50 - Malcolm M. Renfrew, University of Idaho (AC3) (from Regional ConferenceNo. 7) .56 "What Shall We Teach NonscienceMajors?" - EdwardC. Fuller, Beloit College (from Regional Conference No.6) .59 "Chemistry for Non-ScienceCollege Students" - JamesF. Corwin, Antioch College (from Regional Conference No.2) Chemistry for All Students:Introductory "Opening the Doors to .67 Chemistry for Two-YearColleges" - WilliamT. Mooney, Jr. , El CaminoCollege (from Regional Conference No.6)

* Present address:Simmons College, Boston, Mass. Conferences Included in "Selected Reports from AC3 Regional Conferences" (Nov. 1966 - Oct. 1967)

1."Recent Trends in General Chemistry", TexasA&M University, A. F. Isbell, chairman November 18-19, 1966.

2."Chemistry for General Education" and"Balance Between Theory and Description in General Chemistry", Florida State University(Jointly sponsored by AC3 and the Center for Research in College Instruction ofScience and Mathematics), R. Johnsen and G. Schwarz, chairmen, February 24-25, 1967.

3."Teaching Undergraduate Organic Laboratories",Bellarmine College, John Daly, chairman, March 31 - April 1,1967.

4."The Integrated Laboratory", Bucknell University,Lester Kieft and B. R. Willeford, chairmen, March 31 - April 1, 1967.

5."The General Chemistry Laboratory",Worcester Polytechnic Institute(Jointly sponsored by AC3 and the Central MassachusettsSection of ACS), R. C. Plumb, chairman,April 27-28, 1967.

6."Contemporary Development in TeachingGeneral Chemistry", The University ofNorth Carolina at Charlotte, S. L. Burson,chairman, May 12-13, 1967.

7. "New Approaches to LaboratoryInstruction", Washington State Universityand the University of Idaho, Carl Stevensand Elmer Raunio, chairmen,October 13-14, 1967. TEACHING CHEMICAL BONDING TO FRESHMEN Harry B. Gray California Institute of Technology Pasadena, California The electronic and atomic arrangements of matter make up the study of structural chemistry. The importance of this area of chemical study can hardly be overemphasited. Firm concepts of structure are needed in order to explore in a coherent and intelligent fashion the sister fields of chemical dynamics and chemical synthesis. Although teaching structural chemistry has advanced to a higher level than has that of chemical dynamics, it is still a poorly taught subject in many places. We must continue to explore new and better ways of presenting the subject to eager young students who are hearing about it in detail for the first time. Molecular structure can be taught to freshmen at three different levels; these levels correspond to three periods in the history of the subject. The first level covers the period 1860-1920 and includes the models developed by van't Hoff, Le Bel,Kekulg, Werner, and many others. Although these "classical" ideas of molecular structure can be covered rather rapidly, it is worthwhile to present them as the beginning of the logical development of the subject. After all, chemists knew a lot about the shapes of molecules long before anyone had heard of quantum mechanics. Quantum mechanics is even more beautiful when studied after an exposure to classical structural chemistry. Concepts such as covalence (the number of "hooks" an atom has to attach other atoms), oxidation number, coordination number, ionic charge, and their relationship to the composition and structure of matter can be introduced during this part of the course. A particularly good example to use is the list of the numbers of isomers found for chloro compounds with the following compositions:

Composition No. of isomers

CH2C12 1 C6H4C12 3 Pt(NH3)2C12 [Co(NH3)4C12]C1 Facts such as these led early workers to suggest that carbon bonded to four groups is tetrahedral:

1 The three isomers of C6H4C12 an be explained using a planar, hexagonal C6 framework (and introduction of the early ideas of electron delocalization): Cl CI H H

H H

H ortho meta para

The two isomers of Pt(NH3)2C12 show that four-coordinate Pt is not tetrahedral, but square planar: H3N------C 1 1;13N -CT \ /: \ A Pt' Pt ' ' Pt Pt S / / H8N------Clu C1------NH3 Cl------NH3 cis trans

Finally, the two isomers of the ion Co(NH3)4C12+ suggest an octahedral structure around Co:

Cl Cl +

[H3K-1--7113 H4- -,NH3 H1-- , Co , iCo( , Co H314 --?.-11----11H3 H 3N 4---:I1H3 H311------1\11H3 C1 C1 NH3 NH3

From these observations, we assign anumber of directed "hooks" or "covalences" to different central atoms. A largenumber of plausible molecular structures can thenbe deduced from molecular formulas. Forexample, knowing that H has one hook and carbon has tetrahedrally directed hooks leads tocorrect predictions of the shapes of C2H2, C2H4, and CH4:

2 planar ethylene tetrahedral molecule methane molecule

H O. amal MO Is m .ws me ear mor. OM 44a aga gasH_C

linear acetylene molecule techniques to the the seriousapplication of X-ray The discoveryof X-rays and period in thestudy of chemical molecular structureushered in the next determination of available on theshapes ofmolecules and finer de- bonding. As moreinformation became bond energies, a structure, such asbond lengths,bond angles, and tails of molecular needed. Chemistswanted to understandwhy H2 better model forchemical bonding was The big development stable than H or H3,and why carbonhad four "hooks." was more electron sharing inbonds such thateach atomic in this period wasthe concept of to that of aninert gas atom.Thus, we participant achieved aconfiguration equivalent by sharing inthe two bonding represent H2 as HH or H H, in whicheach hydrogen structure. In order like He, whichhas a chemicallystable electronic electrons "feels" with eightelectrons: to "feel"like Ne, carbon mustsurround itself H

H. Fluorinealso wants to this it can doby making fourbonds as in H C

H molecules such as and HE: . achieve the Neconfiguration, explaining central atomeffectively metals, examples canbe cited inwhich the In the transition . achieves the Krconfiguration, as forexample Fe(CN)6 bonding came representationsof chemical The useful rulesof 2, 8, and 18in deducing from the conceptof the stable inert gasconfiguration. It is useful topoint exceptions to therules of 8 and18. Of course,there are many form aninteresting patternwhich out, because theexceptions themselves Representative certain of these of orbitalmodels ofbonding. can beinterpreted later inthe framework

3 exceptions to the octet rule are PF5 and SF6, whereasCr(CN)63- and PtC142-are two of the vast number of exceptions to the rule of 18. The great discoveries in theoreticalphysics in the late 1920's, coupled with substantial advances in the experimental methodsof structural chemistry, led to the development of models of molecular electronicstructure which are still under scrutiny by contemporary workers. Spectroscopic experimentaltechniques designed to explore in great detail the electronic, vibrational,and rotational motions of molecules, gave chemists much needed information on precise bondlengths and bond angles of discrete molecules. Magnetic resonance methods gaveadditional information on electronic structure. The magnetic and electric dipolar propertiesof molecules became known to experimenters. No longer were "lines" sufficient for bonds , nor"dots" sufficient for electrons. Models were needed which allowedformulation of electronic excited states, as well as the ground state. Furthermore, we need to knowthe "shapes of bonds" to interpret many molecular properties. This is the appropriate time to introducethe molecular orbital model. In this model we assume orbitals and discrete energylevels for molecules, in analogy to the modern model of atomic orbitals and energylevels. The properties of bonding and antibonding molecular orbitals are introduced in the caseof H2; subsequent discussion of H2+, H2, He2+ may include interpretations of bond lengths, bond strengths, andmagnetic properties. The shapes and relative energies ofmolecular orbitals for the general homo- nuclear diatomic molecule provide a frameworkfor the discussion of bonding (or the lack of it) in Li2, Bet, B2, C2, N2, 02, F2, and Net.It may be helpful to "derive" the shapes of the molecular orbitals by making appropriatelinear combinations of atomic orbitals.It is probably good to admit straight outthat the relative energy levels come from spectroscopic experiments and from themagnetic properties of diatomic molecules. After ail, atomic energy levels for the many-electronatom are asserted on the same basis and the student already has some mental picturethat an mem level is associated with an orbital. Bond lengths, bond strengths, and magneticproperties can be interpreted for B2, C2, N2, 02, and F2 in terms of the net bond orderdeduced from the molecular orbital structure: Bond order: B2< C24 N2i> 027 F2 Bond length: B2'7 C27 N2< 02< F2 Bond energy: B24 C2C N2? 02> F2

An added bonus from themolecular orbital model is the explanation of theparamagnetism of 02, which is a mystery if each oxygen hasachieved the Ne structure as in :0 . Before leaving the diatomic molecular orbitalmodel, it is a good idea to stress very strongly its highly approximate nature. Thestudent should realize that thismodel is not the last word by any means. Here one ortwo problem spots may be cited toplant a healthy element of suspicion inthe student's mind. One place where thesimple molecular orbital theory fails is in the Li2and Li2+ molecules. The simple theorywould predict Li2 to be more tightly boundthan Li2+, but experimentally the reverse isfound to be true. This puzzling trend should serve tostimulate student thought and discussion. There is a limit, naturally, to the useful extent of development of the delocalized molecular orbital model (for freshman students). Two or three polyatomic molecules as examples, however, will serve as stepping stones to concepts of energy levels needed later for the development of models for metallic bonding and the ligand-field theory of transition-metal complexes. The delocalized molecular orbitals for the linear triatomic molecule BeH2, and the ir orbitals for the benzene molecule, are reasonable choices. After presenting BeH2, the localized hybrid-orbital model can be developed as a means of pinpointing the bonds in polyatomic molecules. The concept of hybridization and the "need" for it is one of the most difficult and important ideas to get across to the student. Hybridization can first be intrOduded in the case of Li2, by pointing out that electron density can be stuffedinto the region common to the two Li atoms by contaminating the 2s Li orbital with a little 2p character. How much 2p character should be mixed in is a matter of some speCulatiOn, but it can be argued that an optimum value (a balance between the larger overlap gained and the higher energy of hybrids because the 2p orbital is higher than 2s) is abOUt 10%..20chara:Cter for Li2. Another viewpoint on the need for hybridization comes from a' disCussioii of, the B2 molecule. The ground state of this molecule is3E, meaning that.th.efe,are two unpaired electrons in the , bonding molecular orbitals. This in turn shoWSthat theirbonding level is filled before the a bonding level constructed from the 2p valence:orbitals.The unexpected, higher energy of the 2pa bonding level can be rationalized:a6a direct 'consequence of the stabilization of the 2sa bonding orbital byhybridizatiOn..;:As.a 'result of the 2s-2p hybridization, electrons in 2sa are more stable, being more 'COnbentratedin the bonding region, but the concomitant and necessary 2s hybridizatiaii.intO 20o :renioves some electron density from the bonding region for this orbital, raising itseneigy. The use of the hybrid orbital model as a means of getting electrOns away from each other should be explained further through the use of several other examples. Good examples are H2O and NH3, where it can be argued that thesp3-is bonding model is better than the simpler 2p-ls model, because the observed bond angles are1:05°.(112.0) and 107°(NH3). The introduction of 2s character into the bond orbitals Provides a mechanism by which the bonding electrons can be better separated, without arl.'r loss of Stability due to a decrease in overlap of the appropriate valence orbitals. Thenthe decreased inter- electronic-repulsions known for 3p orbitals of sulfur atoms (relative to 2p oxygen) account nicely for the 92° angle in H2S. The groundwork has now been laid for a discussion of bonding in condensed phases. This is a very important topic, because most chemistry is not done in the gaseous state. The types of solid lattice structures can be outlined based on the principal bonding force in operation:(1) the metallic bond, characterized by relative freedom of electron movement; (2) the weak van der Waals bond in molecular solids, described as an (instantan- eous-dipole) - (induced-dipole) force; (3) the strong and apparently localized covalent bonds in the non-metallic network solids; (4) the ionic bond, found in lattices such as NaCl. The types of bonds found in condensed phases are directly related to the electronic structures characteristic of the atoms and simple molecules which make up the materials in question. This relationship is a big bonus to the student. The transition metal complexes are excellent subjects to use in illustrating the utility of molecular orbital theory.In our opinion, far too little attention is given to this vital area of modern chemistry. With a background of molecular orbitals and energy levels in molecules such as H2, N2, 02, Bel-12, and C6H6, it is relatively easy to intro-

5 duce the idea of a splitting of primarily d orbital energylevels in octahedral complexes because of covalent bonding. An explanation ofthe colors and magnetic propertiesof selected octahedral complexes should be presented. It is in the spirit of historical presentationof concepts of molecular structure to outline briefly the hybrid-orbital theory for two orthree complexes.It can be pointed out that the interesting colors ofmetal complexes could not be explainedusing the hybrid-orbital theory of localized bonds. Thecrystal-field model takes a 180° turn away from the hybrid-orbital model, itsbasic tenet being that the electronicstructural properties of metal complexes can be interpretedwithin the framework of an ionic model.This model lends itself to classroom presentation,because it is relatively easy to convince the student that in an octahedral crystal

octahedral crystal field field of point charges the five metald orbitals are not of equal energy. Thisleads to the assertion that there are in fact twod orbital levels, called t2r, and eg, andthat they just happen to be split by about the energyequivalent to visibleli'ht frequencies. Thus, the colors of most metal complexes occurbecause of light absorption accompanyingelectrons jumping from the lower t2glevel to the upper eg level. It is wrong to leave the student atthis point. Recent calculations andcorrelations show that this electrostatic part ofthe t2 eg splitting is not nearlylarge enough to explain the effect; furthermore, itis ofth%wrong sign! The latestviewpoint is that covalent bonding involving the c dorbitals(dx2yz,dz2)in the usual notation) gives a bonding da level and an antibondingda level. The antibonding dolevel is the eg level of crystal-field theory, but the majorcontribution to its instability relative tothe t2level is due to its involvement in adelocalized amolecuiar orbital network. No newco%cepts are needed inorder to discuss energy levels in metalcomplexes. The origin of the splittings in molecular orbital levels isthe same as in H2 and benzene. Concepts of chemical bondingand molecular structure can beprofitably used and strengthened in a tour through representativeparts of the periodic table.In thisall- important part of the course, it is agood idea to discuss thechemical transformations of molecules as a systematic functionof structure. Some nonmetallic elementswith rich structural chemistry are boron,carbon, nitrogen, oxygen, phosphorus,and sulfur. A great many structure-reactivitycorrelations can be made using theseelements as examples. THE GENERALCHEMISTRY COURSE: TENTATIVE SOLUTIONS SOME PRESSURES,PROBLEMS, AND Robert I. Walter Haverford College Haverford,Pennsylvania general chemistry afternoon is notto give you"the word" on the My purpose this All of us mustdesign our pro- far as I amconcerned, thereis no "word." course. As of the studentswho happen to come ourway. grams tofit the abilitiesand backgrounds directions in whichthe generalchemis- survey whatseem to meto be the I would like to moved during the recentpast. try course,with manyexceptions, has uniformity in the waychemistry was taught Until 25 years ago,there was a dreary chemical equilibrium Students attended ageneral chemistrycourse--some in this country. completed a year ofanalytical chemistry, and a lot ofdescriptivechemistry--and then chemistry and of organic. Intheir senior yearthey studied physical followed by a year advanced work.Teaching has become perhaps had anopportunity to take asemester of variety of new 25 years becausepeople have tried a much more excitingover the past subjected to a numberof schemes. Theundergraduatecurriculum has been course and many of thesepressures focus onthe freshman course. pressuresduring that period, than about thecurriculum ingeneral. I shall try to saymore aboutthe freshman course demands of students on is the studentsthemselves. The One source of pressure would have beenthe case 25 these days aremuch moreoutspoken than to be their education know what theythink. They arejust as inclined years ago.Students now let us views as theymight have been short-sighted, and in manywaysprejudiced in their teach- and one can'tget away fromthem if one is earlier. These areproperties of youth, student pressures, There have beenall kinds of responsesto these ing young people. strongesteducational institutions. curriculum changesin some of our chem- and these include emphasis on andearlier presentationof quantitative Two examples arethe reduced istry, and thedevelopment of coursesin biochemistry. chemistry. the rapid rateof change inthe practice of A second sourceof pressure is analytical chemistryalso. Twenty- illustration of thishas to do with analysis, a sem- The most obvious semester ofsophomore qualitative five years ago mostschools offered a curriculum there was athird semesterof and some timelater in the and ester of volumetric, one offered acourse ininstrumental analysis, gravimetric analysis.At that time, no work. The needfor this relatively fewinstruments in usein analytical indeed, there were century. Thispattern was a sortof vestigial course is adevelopment of thepast quarter the days whenmost the chemistryprogram.It came from remnant; a kindof appendix on became rockanalysts. Naturally, wein- completed a degreein chemistry supposed to chemists who to offer thesecourses. They were vented various excusesfor continuing chemical equilibriumcalculations. technique,descriptivechemistry, and argu- teach laboratory that they did anyof these. Thereis one very strong There is good reasonto doubt the interestwhich many students qualitative analysisin the program: lesson ment for keeping laboratory work,and I think thereis a serious take in it. Theyreally enjoy the problems for themwhich they have to They enjoy itbecause it poses laboratories which for us in this fact. find other waysto give chemistry solve for themselves,and if we can

7 also pose problems for the students, these will be equally attractive to them. Careful analytical work is rarely a source of pride or satisfaction to students today, and this may be bad for the future of the science. Not all problems can yet be solved by compu- tation! Another source of pressure on the freshman chemistry course is the improvement in high school curricula.If anything, this has made it harder for us, because we are now faced with a wide range of student backgrounds from no chemistry at all to the equivalent of a good college course. Worse yet, many students come to us thinking they know material which they really understand very superficially. Obviously we must provide for a great deal more flexibility in assigning students to thefreshman program than was necessary 25 years ago. This is very difficult. Many of us have foundthat the best way to judge is to test their mathematical ability. This is a matter which I have never under- stood, because the selection of material usually presented in this course does not demand a great deal of formal mathematics. The requirement seemsinstead to be an ability to reason in the abstract which students usually do not pick upif they have not acquired reasonable facility in mathematics. Still another source of pressure, reflected less in the freshman course than in the rest of the curriculum, is the graduate schools. Many of these now expecttheir students to select a research advisor and a problem within the first few weeks they are in the school. A student who has had some exposure to a research problem while an undergraduate has a much better chance to make this decision wisely.It is not unduly cynical to say that graduate schools expect more of the undergraduate program every year;they seem to be moving toward a requirement thatall courses be out of the way by the time a man is admitted to graduate study. The time may be comingwhen those of us who believe in a liberal education must resist this trend, for we may be reaching a stage at which we train chemists, but no longer educate people. There are also pressures on the curriculum and on the freshman course which arise from industry. Most of these take the form of a question. Why is it that you people don't teach "blank" to your students?"Blank" here is almost any topic in chemistry: surface chemistry, polymer chemistry, literature chemistry, chemical economics, and so on. Pressures of this same type arise fromthose of us who teach. All of us tend to reflect our own prejudices in our selection of course material. There is much to be said for teaching those areas in which one is most interested and most knowledgeable, but I think one has to maintain a perspective over the entire field of chemistry while he does this and sometimes we do not manage this. Now, I should like to say something about the directions in which I believe the chemistry curriculum has moved. One of these I have already mentioned. Qualitative analysis used to be a sophomore course for everyone, became part of the freshman course, and has now disappeared altogether in manyinstitutions.In some cases, quantitative analysis has also moved into the freshman course. This is possible at a serious level only if the student body is quite homogeneous. Both manipulativeand intellectual deficiencies can cause problems here. The general chemistry course isfor all of us the massive course which requires handling the largest numberof students and the largest proportion of physically or intellectually inept students. When one moves new topics into the freshman course, arelatively unselected segment of the student body must then be brought to mastery of this material. The problemof physical ineptitude may become quite serious as the American population becomes increasinglyurbanized, with little opportunity formechanical experienceduring childhood. topics from similar problem appears as aconsequenceof the transfer of A somewhat the past twodecades. This has physical chemistry intothe general chemistrycourse over level of reflected in all of therecent textbooks.It implies a happened everywhere; it is be expected ofthe large cut of mathematical sophisticationwhich cannot realistically students who enroll ingeneral chemistry. chemistry in theintroductory coursehas been The increasedemphasis on physical have decreased emphasis ondescriptive chemistry.The consequences accompanied by a amount ofdescriptive chem- been aggravated bychanges which havealso decreased the to believe school courses.This may be amistake, for there is reason istry offered in high enthusiastically whenthey are younger.Their that students masterfacts most easily and factor in the reasoning or originalthought developslater. A possible interest in logical introductory course isthe parallel declinein lec- decline of descriptivechemistry in the activity might be to accumu- One valuable areaof future Council ture demonstrations. their new cousin,lecture experiments, late ideas for eitherlecture demonstrations or ideas in research inthe appropriate areas.These undeveloped from chemists active financial supportfor investigation could then be madeavailable togetherwith modest of work shouldinterest many collegefaculty mem- during the summervacation. This type demonstra- do it well, and theresult could be acollection of lecture bers. They could developments in thescience. Manycollege teach- tions and experimentsbased on modern develop ideas onwhich to basedemonstrations, and few re- ers are notin a position to them properly. search people arewilling to devote timeto developing trends in planningand teaching the I should like now toturn to some apparent chemistry to the first The transfer oftopics from physical general chemistry course. I believe that itis possible toteach course has inthe past beenrather indiscriminate. but only if one iswilling to take enoughtime to do it properly, any subjectto a freshman, which we have madein the recent at the expenseof other topics. Oneof the mistakes chemistry at a teach freshmen toowide a range oftopics from physical past is to try to understanding. There nowappears tobe a level which is toosuperficial for thorough but each of them insubstantial detail.Together with trend towardteaching fewer topics descriptive material so asto illus- this , an interestis developing inarranging selected principles which havebeen coveredearlier.Efforts in this direction trate the theoretical but it seems likelythat this have been handicappedby a lack ofappropriate material, chemists hope that number of textswhich are now beingwritten. Many will appear in a rationalization of theentire undergraduatecurriculum in these changes willbe part of a of the program. A program chemistry, based upon athorough analysisand restructuring for some years atEarlham College, andanother modified in this wayhas been in use that the first coursein the latter scheme has beenproposed at Cal Tech.It is interesting program isstill called generalchemistry! APPLICATION OF A RESPONSESYSTEM, TAPE RECORDED MATERIAL, AND OTHER NOVELTECHNIQUES IN UNIVERSITY CHEMISTRY INSTRUCTION Brian D. Pate

Simon Fraser University Burnaby B.C. , Canada at Simon FraserUniversity has exploredthe application of a The Chemistry Department laboratory courses at theuniversity number of novel teachingtechniques in lecture and freshman level. conventional overhead projectorsand FM In lectures to groupsof up to 550 students, projectors is prepared in radio microphones areemployed. All materialfor the overhead provided at cost withphotocopies of all projectedmaterial. Stu- advance. Students are attention to the lecturer. dents then concentrate onmargin annotations and pay more experiments are shown anumber of ways. A modifiedoverhead Lecture demonstration color or transpar- projector system is usedto display experimentsof the Alyea type where television projector and TV camerason the lecture po- ency are important.A large screen in other ways more dium are used to projectexperiments which are opaque,or which are Experiments involvingnon-portable distantequipment are first suited for the TV medium. 35mm slides and 16mm video taped and thenpresented later in thelecture auditorium. movies are also insertedin the lecture sequencewhere appropriate. particularly in tutorials orproblem working sessions, anelectronic In lectures, and the auditorium is equippedwith response systemhas been employed.Each student seat in lecturer's podium indicatethe percentage ofswitches a five positionswitch; meters at the students to convey in the room dialing aparticular position. Thissystem is used to allow their degree of understandingof a particular item.The system anonymously to the lecturer completed the working is of most use whenstudents convey to thelecturer that they have that they are havingdifficulty with a particularsegment of it. of a particular problem or student and the lecturer verymuch improved but Not only iscommunication between the capabilities of the audience. the pacing of material canmore accuratelybe gauged to the routinely recorded and madeavailable later for studentreview in a All lectures are which review the workingof listening facility.In addition, taperecordings are available problem sets and whichprovide supplementarylectures on difficult areas. laboratory, coupled with an Recorded materialhas also been employedin the freshman for each student. Thelatter is 6 feet in widthand is surrounded individual laboratory booth booth contains all thechemicals and glass- by walls extending toabove eye level. Each and 8mm loop pro- ware required for agiven week's experimenttogether with a tape player jector as may be calledfor. decoupled Students may enter and leavethe laboratory at anytime; their schedule is staff by the use ofrecorded materials.The material offered in from that of the instruction the materials in a booth may a given week isnot limited to oneweek's exercise, since experiment to anothershould a student requestthis. Students readily be changed from one intercom unit who experience difficulty mayobtain advice or summonhelp by means of an in each booth. Staff spend much less timein the repetitive instructionof routine techniques. They spend more in individualcounselling of students and onchecking for unsafe practices. Each student each week isexamined by a ten minute quiz inaddition to inspection of his laboratory notebook. Thisweekly session also provides anopportunity for individual difficulties to be ironed out. The capital expense of thislaboratory is not appreciably greaterthan that of a conventional laboratory course. Thisfollows from the fact that expensiveitems such as balances are not all requiredsimultaneously by the students and asmaller total number is adequate. This offsets the cost of taperecorders and other special items. The reception of these techniquesby students has been generally afavorable one. This extends beyond the merenovelty effect, which howeverby itself may be an appreciable teaching aid.In general we are encouragedand intend to pursue this line ofexperimenta- tion.

References: A Response System InUndergraduate Teaching. B. D. Pate. CanadianUniversity May -June 1967. Application of Audio Visual Aidsin an Undergraduate Chemistry Laboratory Course. N.Flitcroft, E. Wong, and B. D. Pate. Chemistry inCanada (in press). THE INTRODUCTORY LABORATORY -IDEALITY VS. REALITY Richard J. Kokes

The Johns Hopkins University Baltimore, Maryland The thing I would like to talk aboutfirst is something on which I think mostof us can agree, that is, theideal laboratory. We all know whatit should be. Then I would like to talk a little bit about the reallaboratory.Finally, I would like to add some commentary -- the prejudices that I havedeveloped over the years. I think that we will all agreethat the first requirement for theideal lab igthatwe have an ideal student. We wouldlike this ideal student to be able,interested, and to have lots of time. Now we get tothe harder part because in additionto an ideal student, we also need anideal teacher.In the order of decreasingimportance, the teacher should have lots of time available andhe should be able and he should beinterested.(You can argue about the orderbut certainly these areingredients.) This ideal laboratory should have a kind of apprentice - masterrelationship,say,with an instructor who hasonly two students to worry about. Then we add tothe ingredients of the ideal labwhat we are going to do.First (if you think you haveheard this before, you mayhave) we would like to teach some basictechniques and methods. We really wantto teach them more than basic. techniques, however; wewould like to show them that there are someregularities about chemistry, there are someexpectations in the behavior ofchemical systems that we hope will befulfilled. After we had led him downthis garden path, we wouldperhaps like to show him that not all systemsbehaved ideally.In other words, if you want a very primitive kind of example, first weput him to work with theideal gas law using helium and then we give him somethinglike acetic acid vapor as a casewhere ideal behavior is not followed. This is aperfectly reasonable thing provided we cando it without making it too complex. The thirdthing we want to be able to do is to answer aquestion something like this: do the irregularitiesstem from something in nature orsomething in the technique? In other words, if hefinds out that PV is apparently notequal to nRT, is this just because n and R and T arenot too well known, orthat his measurements are not accurate enough or that PVis not equal to nRT in thisparticular case? This is very important. The fourth item,which is really a part of the third,involves the development of what we might call criticaljudgment.I think we have to give him achance to test what he suspects. In otherwords, give him a chance to repeathis measurements, to perform to design an alternativeexperiment.I think these also are in replica his experiments, is the kind of ingredients youhave in a research problem.If you run into something that unexpected, the first thing youdo is design an alternativeexperiment to try out your explanation. This is the ideallaboratory. Now I will go over to areal laboratory.In order not to insult anybody, Iwill talk I will about the laboratory whichI will say we have at JohnsHopkins, a real laboratory. discuss how well, howclosely, we approach the ideallaboratory.First of all, let us look at our student the country over.(I refuse to look at the instructor.)Of all the stu- the freshman chemistry course,(something like 400,000 dents we collectively feed into Ph.D. in chem- or 500,000) only0.3% end up going tograduate school and getting their istry; 99.7% of them goelsewhere. Let's assume that the0.3% going on to get their Ph.D. in chemistry are able,interested,and have lots of time, that is,0.3% of the stu-

12 dents are ideal. The point that I amtrying to make is that if we say that wedesign the course entirely for thechemistry major with the idea thatthey all do research in graduate school, we are considering only a verysmall fraction of the total. We have todesign chemistry for all types of studentsand I think that this is probablybest anyway. But it may well be that thosestudents who are truly interested are aminute fraction of the total. As I said earlier I refuse todiscuss the teacher. Obviously theyhave an ideal teacher. Some years ago we revamped ourlaboratory and we did not simply movedown things from the physical chemistrylaboratory -- although it may look that way --but we actually decided what experiments would beinteresting to do. Then we wrote thebook on the basis of these experiments. When,after the first year, we questionedthe students as to what they thought about the course,their principal complaint was thatthere was no correlation between the lectures andlab. At that point I decidedcorrelation is a problem that had no solution so I haveforgotten about it. I think maybe, we can bestdiscuss the real lab in terms of thefour points cited in our discussion of theideal laboratory. We achieve thefirst objective and teach them some techniques andmethods.If we look at the second, i.e., weshould demonstrate for them that some systemsbehave ideally, I think we can'talways do this from the standpoint of the students. Inother words, the systems on whichthey do gas law experiments should really obey theideal gas law but according to theirresults they often do not. Point number three: Is thisirregularity due to nature or is it due totheir experimental techniques 2 Well, they make astab at this sometimes in theirlaboratory reports. The big drawback to this particularreal lab, and I suspect to many,is that there is very little of this kind of process thattakes place. They get their results,and there is always a question: Are their results correct ornot? There is very little opportunityfor them to go back and redo the experiment, andthere is very little opportunity forthem to devise alternative experiments to check outtheir hypotheses. I think the real trouble with mostreal labs is a number of things.Let me review for you a little bit of thehistory of our lab at Hopkins. Thefirst year of the new lab, confused -- the students didn't mindthough, they thought things were pretty horrible, diffi- we were doingsomething for them. The second year wehad ironed out most of the culties -- things ran a good deal moresmoothly -- we were able toanticipate some of their problems. You see, thefirst year we were 2, 3, or 4weeks ahead of these students. We had outlines of what wewanted them to do and we gotthe apparatus into the lab sometimes five minutes before they came.We had tested out theexperiments on a small scale with two students, and then wehad decided whether to go intofull scale operation. At any rate, the first year waspretty bad. The second year wasmuch better. Everybody was enthusiastic. Bythis sixth year we have taken careof almost all the quirks thathad existed. We now have theprocedures pretty well worked out sothat the students can follow them in detail. We haverealistic schedules, so much foreach experiment -- some experiments taking as long as amonth. We also have fraternityfiles filled with what the results should be on the experiments,and so if the student really getsfouled up he can find out what the answer should be.Finally, we have inertia onthe part of people connected with the course. By thissixth year we are well organized.We are well organized and deadly.I think much of the enthusiasmhas gone out of thislaboratory by now. OK, so that's areal lab.

13 not necessarily Let's talk now about someof the prescriptionsI would make, but first of all we have toobviously be aware take. What do I thinkcould be done? Well, could be done as anal- that 99.7% of thestudents aren't ideal bydefinition. What else laboratories? This issuehas been discussed alarge number of times: ternative to the possibility of laboratoryby film or TV. there is a possibilityof film loops, there is a is like old age: There is all this sortof thing.In at least one,however, the laboratory neither is too badcompared to thealternatives. soup up things alittle bit in the lab bytrying lecture ex- I think perhaps you can Campbell in the Journalof Chemi- periments. One of themI recommendhighly -- (by Art try it three years ago) isthe blue bottleexperiment. Read it over, cal Education about of your own. Thiswill tell you out -- it's lots offun and see if youcan't work up some I think that there areprobably many thingsthat you what a lectureexperiment is like. without laboratory that you canactually accomplishin a lecture experiment aim for in the like the real experience.You have to get the going to the bench,but nothing is quite how much to add tothat students to the pointwhere they have tomake decisions about trivial things likewhich beaker shouldbe used to put and how much tothis -- even to Justification for itsexistence. something in. Thesesimple aspects oflaboratory are ample however, is that the neweryour laboratoryis, almost regardless What I would suggest, the ideal lab, andthe older it is the of what you aredoing, the closerit's going to be to closer it is going tobe to the real lab. THE INTRODUCTORYCHEMISTRY LABORATORY Richard J. Kokes

The Johns HopkinsUniversity Baltimore, Maryland sub-topics. These are: I wouldlike to divide mytalk into a half-dozen I. A CommercialProcess (of interest toacademic chemists) 2. Then and Now 3. Prophecy 4. Ideality vs. Reality 5. Alternatives tothe Laboratory 6. A Message deal with theintroductory laboratory,but we shall not All of thesetopics, of course, which, of course,impose restraints ignore in ourdiscussion the lectureand later courses on what you cando in the laboratory. 1. A CommercialProcess chemistry. Roughly 106 high school studentstake a course in Each year roughly college chemistry courseso that atthis step, we half this numbertake an introductory college course (In reality, we haveless because manywho take the have a 50% yield. course.) Of this startingmaterial,106 students, we end up have not had thehigh school this two-step processgives 104 students graduating aschemists. Thus, with a yield of prejudice, we focus ourattention on theresearch chem- a yieldof 1%.If, with a common obtain their Ph.D.'s. the Ph.D.'s, wefind about 1500 to2000 students will ists produced, has an ultimateyield of about0.2% (or 0.4% based on Therefore, thismultistep synthesis colleges alone). tend to put most face of the abovestatistics, however,most chemists Even in the of students who go onto get theirPh.D.'s. Furthermore, of their effortsinto the 0.3% in mind. The introductory coursewith only theneeds of the 0.3% we oftendesign the "Engine Charlie"Wilson: "What'sgood taken parallels astatement of chemists attitude commonly the whole U.S."Chemists say:"What's good for for General Motorsis good for appealing, may notbe true. is good foreveryone." Thisargument, while judge the success point that causes mesome concern.We tend to There is one other produce.I think we are chemistry courseby the numberof majors we of our introductory demonstrate to astudent that chemistryis not his doing an equallygood job when we is not easy toapply nor does itprovide kettle of fish.I realize thiscriteria of success to judge the for deans,heads of departments,etc. Nevertheless, convincing arguments is probably afraud. success of a programby the numberof majors alone 2. Then and Now table re- I define then as1947 and now as1967. The accompanying To be specific practiced by anumber of institutions. presents thecurriculum thenand now as

15 1st year 2nd year 3rd year 4th year qual. Physical Then Intro.Inorg. quant. Organic Chem. Adv Quant + others Inorganic Now A. Intro.Chem. Organic P. Chem. qual, quant. Adv.Quant. + others or B. Intro . Chem . P. Chem. Organic Inorganic qual, quant + others curriculum is the most common,but I think we find this form at I don't mean the "now" for most forward-lookinginstitutions.It probably representswhat the average curriculum majors will be shortly.

3.Prophecy If a chemist trained in thethirties or forties was putinto suspended animation, and put into an IntroductoryChemistry course, he would say, then resurrected in 1967 honest and call the intro- "Aha! Physical Chemistry."Perhaps by 1987 we will be more ductory chemistry course with itsattendant sophisticationPhysical Chemistry. Then in will probably take what we nowcall Organic Chemistry with the second year the student with names we some admixtureof Inorganic Chemistry.Following this will be courses probably deal with the moremathematical aspects of struc- haven't thought of that will the way out. ture. Quantitativeanalysis as a separate coursewill vanish--it's already on For what it's worth,this is my guess. that There is anotherpo'ssibility, however. Hammond atCal Tech has proposed divisions of chemistry intoorganic, physical, inorganic,and analytical the traditional is very strong. For example,the inorganic be reexamined.Overlap of these divisions weight. chemistry of complex ionsoften deals with compoundsthat are mostly organic by that we adopt divisionssuch as: StructuralChemistry, Chemical Hammond proposes inorganic and Dynamics, Syntheses,Energetics, and TheoreticalChemistry. Clearly, the studying mechanisms ofreactions are more closelyrelated than they are organic chemists chemists are studying to syntheticchemists (organic orinorganic); the first group of according to Hammond. Giventhis point of view, our coursesshould chemical dynamics Dynam- reflect this newer, moremeaningful, division. Thisimplies one year courses in Synthesis rather thanphysical chemistry, organicchemistry and in- ics, Structure, and it is my belief organic chemistry.Although the logic ofHammond's position is obvious, this new labelling schemewill not become wide-spreadfor at that the changeover to (It is amusing to note that with least a generation.Chemists are very conservative. chemistry, the first year courseof the proposed newcurriculum is this new labelling of package now actually being called--"General Chemistry."This is the only part of the tried at Cal Tech.) 4.Ideality vs. Reality In my mind's eyethe ideal lab shouldpermit the following: a. Teachthe student basictechniques. b. Show the studentthere are regularities inchemistry -- predictions he can make withreasonable hope of theirbeing correct. c. Show thestudents not all systemsobey these predictions. his results or evendesign alternativeexperiments d. Permit him to recheck fault so that he candecide if the failure of hisprediction in case c is a of nature or his technique. chance to subject hishypothesis to experimentaltest. e. Give him a and experimental de- One of the most importantaspects of the aboveis decision-making the true flavor of thelaboratory in real sign by the students.It is here he captures to students- - chemistry. This, I believe,is why qualitativeanalysis generally appeals Quantitative analysis isgenerally boring and it hasunknowns. not the unknown aspect. qual., properly presented,offers both a But quant. also hasrigid procedures whereas alternative standard procedure and anopportunity for students todesign and carry out experiments. at Cal Tech by The closest to theideal lab (by mycriteria) is that currently in use broken down into eightlab sections of Gray and Hammond.The sixteen students are this is truly an two each. Thus, onepair of students has Grayfor a lab instructor. relation--with a mostenthusiastic teacher.)Initially, they apprentice-master kind of it.In the synthesize trisacetonylacetonatochromium(III), purify it and characterize characterization they can useseveral methods:analysis, spectroscopy,paramagnetism, but the student has someoptions. After this etc. Severalcross-checks are required, ligands, nitrate the student can carry outfurther synthesis, e.g.,he can brominate the again purify the productand use severaltechniques to charac- them, etc., but he must by the terize it. From the start anumber of options are available asto the path chosen professional standards incarrying out these steps.Future student, but he must use It has been empha- plans call for reactivitystudies on the student's ownpreparations. such a program must beflexible and provide lots oftime for the sized that for success for both student andteacher. student.It sounds to me likethis is an exciting experience than two students perinstructor and more thansixteen Most real labs have more alone raises students in toto. AtHopkins we have slightly over300 in the course. This some logisticalproblems and we oftencompromise with reality. Let me first talk ofcorrelation of lecture tolaboratory. Some years ago, we com- Hopkins. First, we gottogether a series of experimentsthat pletely revised the lab at Then we wrote the we thought wereboth interesting to studentsand rich in concepts. of this procedure was toemphasize the correlation ofthe two. lectures. The purpose of their At the end of the year wepassed out a questionnaireto the students. One lack of correlation betweenthe lecture and the lab.I think principal complaints was student has this correlation aspectis a bugaboo we should getrid of. Provided the the lecture to understandthe procedures, weshould not sufficient background from ,only is strive for aone -to -onecorrelation between lectureand lab.I now believe not be impossible from thestudent's viewpoint.Furthermore, if it unnecessary, but it may position compared to the we achieve aforce-fit, it may relegatethe lab to an inferior lecture. first year Let me return to generalimpressions of the lab courseat Hdpkins. The demanding. All instructors wereonly one step aheadof the of the new course was quite but ,this just showedif student.(Testing, of course, had beendone over the summer, the experiments werereasonable, not the student'sreactions to them.) Schedules were very flexible and could bereadily expanded if the need arose.Often, we fouled things up. The students didn'tmind, however. They felt we weredoing something for them. By the second year we had manyof the difficulties in handbut not all. The students were even more enthusiastic.By the sixth year all thequirks were taken care of.Various "saves" along the way were availablefor the student who fouls uppart one of a sequence. Schedules were tightened up. Fraternityfiles were full of old reports.The professor in charge can now rest easy--everythingis organized--all instructorsknow what to do. Somehow, however, some of theexcitement, the newness, theenthusiasm, the investigative aspect has gone out of thelab.I firmly believe onceinertia governs a lab program, rigor mortis is setting in. Thisis one of the principalproblems with a real lab. 5.Alternatives What are the alternatives tothe lab? The onesconsidered by AC3 in a recent report are: films, TV,programmed learning, andlecture experiments. Forall the real problems connected with a reallab, the lab--like old age--isnot so bad when you consider the alternatives. The most interesting(to me) of the proposed alternatives(as a teaching aid, not a substitute for lab) is the lectureexperiment. A lecture experiment,according to Art Campbell, its principal proponent,is not a demonstrationbut a real experiment. In my the lecturer walks intoclass and says: "Today wewill per- view of a lecture experiment, First, form an experiment with theequipment you see on thisdesk.I will play two roles. hands.I will do what you tell me.Secondly, I will be I will be your technician--your its de- your researchsupervisor.If you propose an experiment,I will try to poke holes in If I can't, we'll try it out.Now, just to get you started,let's see what happens sign. observation. Then the class when we*." Somethingappropriate is done at * to start an is quizzed. Whathappened? Did it happen immediately,slowly? Such direct questions directed to individualsusually generate blank looks.Then you warn them to watchand record observations and yourepeat the initial action.You're off!From here on dialogue determines the course of theexperiment. The lecturer has toshoot down their explana- tions by logic or havestudents design experiments to testthem.It's exciting and trying to the teacher, andI presume effective withstudents.

6.The Message the My message is simple.Experiments in the laboratoryhave to be tailored to all Their needs vary from school toschool. Work up your own setof students in the course. it makes experiments and change themfrom time to time.It avoids inertia. Although scheduling difficult andpromotes disorder, it also providesthe student withexcitement he is an investigator.If you take such an approach,the student will and a feeling that much better not make use of everyminute in the laboratory, but thetime he uses may be spent than in a"packaged lab" that "works outright" with a tight schedule. typified by the I would furtherlike to call your attention tothe lecture experiments in the journal of ChemicalEducation with a "script" by ArtCamp- "Blue Bottle" reported time well- bell. Time taken fromthe lab for experimentssuch as this is, in my opinion, spent. PROGRAM PLANS FOR A CORECURRICULUM LABORATORY Gilbert P. Haight,Jr. University of Illinois Urbana, Illinois early in a teaching careeris that you findout One of the thingsthat happens very jokes and out of touchwith the youngergeneration through your how quickly you get things" that theyhaven't experienced.The through your referencesto "contemporary at brought up short wasat a lecture to somehigh school students last time I was really The introducer decidedto give them mycom- Binghamton, New Yorkabout two years ago. exhausted at the endof history and it took20 minutes. Being pretty plete professional enthusiasm for the meetingby saying, "Havetest this, I got up andtried to generate experience and they alllooked at me ratherstonily. Even my TV tube! Will travel!" , of being, not onlyup-to-date, but was out ofdate. And therebyhangs our problem--one I should like tomake just a few remarksfrom my own self- rather futuristic aswell. "Curricular Response to aChanging generated thoughts onthis problem whichI entitled educators we find thatsociety is using us to preparethe World,"I have noted that as education. Our for the world bypassing on its ownexperience through next generation for what's in storefor the next generation,for a major own experienceis pretty passe changes very rapidly.This is an feature of our experienceeven now isthat the world that daily makes ourtask more difficult.I thought with some accelerating phenomenon present as anIndian agent inArizona at the amusement recentlythat my grandfather was earth in a and lived to "see"the Russian Gagaringoing around the capture of Geronimo' lifetime. Then, again,being a parent with teen- sputnik. That's quite achange for one how right they are a who inform medaily on howout-of-date I am, I think age children utterly in shapingthe_r own views and ownthink- lot of the time toreject our experience cognizance of and then, often Ithink how wrongthey are not to take ing about the world; secured. We havethe problem ofdefining for our- those permanentvalues that we have both permanentand worth passing onfrom our ex- selves and the nextgeneration what is them for change? our ownexperience withchange to prepare perience. How can we use just becoming awareof it. I think that thisis a hard problemand that we are for chemicaleducation has alwaysbeen a The selection andpackaging of material other subjects. Onehas It has been aproblem because wedepend so much on problem. to be a goodchemist. One has tostudy German, or one to study math,to study physics that they translateeverything for (Now I understand theindustrialists to say used to. with languageanymore.)I still think it isuseful their men so theydon't have to bother freshman coming to in chemistry toknow German.Now, imagine a for communication having beenfascinated by hisGilbert chemistry college unprepared inGerman and still, required courses,culture study chemistry.How can weinclude all the set, wanting to needed for the junioryear, andfeed the naturalinstinct courses, andchemistry courses have an impossible be very interestedin biologicalsystems too? We of most chemists to crowding has been afeature of chemistryfor a long time. crowding of thecurriculum. This about our curriculum,thinking more I think in a sense weare moreconditioned to thinking practices so that we canwork in neededsubjects, than others, about streamlining our satisfied with thekind of job we doin this regard. and yet I don't think anyof us is really material about which level, we are notonly expandingthe amount of Now, at the research students, but we areexpanding the de- we can talk,about which we wantto talk to our tails about the material already in ourrepertoire.Just think about where in yourchemical training you learned the things you areteaching your freshmen. You willfind that a lot of it came after your training wasformally finished. And yet a lothappens almost daily in the chemical world that isaccessible to you and to the freshmen.There is nothing difficult about discussing xenontetrafluoride and yet that came into ourexperience no more than two orthree years ago. The hard fact for us as teachers isthat in order to bring students tothe frontier and have them prepared to be chemistswhen we give them up to the world, we aregoing to have to g:'ve up in our teaching muchthat is very dear to us. Thatfirst intellectual excitement of working out a laboratoryproblem, a research problem, orjust a problem (of a particular kind) in a text that reallyappealed to us--that really hit thespot--that got us into chemistry in the firstplace--may be something that isn't partof the basic, fundamental material which must alwaysbe part of the chemist's repertoire.We have a problem that existed in a mythical stone ageuniversity described in a popularmagazine a few years ago. Theircurriculum contained three courses.They taught Fire-making, of obvious utility for the world intowhich their students were going.They taught Stone Working, and they taught Saber-toothTigers. Saber-tooth tigers wereextinct but they thought they should keep it in thecurriculum for cultural purposes. Nowthat's not, per se, a bad thing. We mustkeep our heritage in the curriculum forcultural purposes to a reasonable extent, but the Saber-toothTiger poses a dilemma. How much can wediscuss him without delaying unnecessarily astudent's professional progress? Howmuch can we ignore him without impairing thestudent's basic understanding of hissubject? We have our own saber-toothtigers in chemistry. We havethem in our college curriculum as a whole. What can we afford todispense with in order to prepare the studentfor, not the next world, but the nextgeneration of this world? I think the dilemma I encounter most,the most hindering at least tochanging curricula in chemistry, is the dilemma ofwhat we call descriptive chemistry.I think on the surface at least, and really a greatdeal below the surface if we examine why wedo chemistry- - why we study chemical systems--whatis the end of our efforts, we find thatthe end is the descriptive material we want toknow. We also want to understand themeaning of our knowledge and that is part of the end.But the knowledge itself put awayin books where it is accessible to the nextgeneration, used by them, is certainly anend in the study of chemistry. It hurts, and is painful to say,that this piece of knowledge which Iknow and of which perhaps I was a discoverer orco-discoverer, has to be edited out of my coursefor the next generation. Thefact isthat this editing has been going on,and it has been going on a long, long time. Forexample, a few years ago I becameinterested in the reduction of nitric acid. When Ireduced nitric acid with stannous ion in excess,four equivalents of oxidation tookplace per mole of nitric acid.If you look up your list of nitrogen oxides, you will findthat N20 has the right oxidation number tobe the product of this reaction. Our"descriptive chemistry" tells us that nitricacid is reduced to NO in dilute acid and NO2 in concentratedacid.I thought I had discovered a newreaction of nitric acid, giving N20 as aproduct.I checked the literature and foundthat this reaction had been done before, notby one of my contemporaries, but in1829 by a man named Gay Lussac, of whom you mayhave heard. The reaction of aqua regiawith stannous chloride was a saber-toothtiger in a sense.It disappeared from generalknowledge, but no one kept it in the curriculum for cultural purposes.There isgreat detail in Gay Lussac's writing about this reaction.It was a preparation for laughinggas--he gave instructions It was rather interestingreading, but it has notbeen deemed on how to avoidexplosions. isn't in any advanced in- so fundamentalthat it would be pertinentfor textbook work, it advanced material.It is a fact probably asimportant in itself as organic books, it isn't will disappear oneday. a lot of factsthat we now use in ourteaching. Maybe they too what happens to descriptivechemistry and what isperhaps wrong Other examples of doing the editing job with descriptivechemistry that should give ussome heart about the nitric acid givingNO which are halftruths.I are the numberof things in texts like student for balancing, think if you took a listof redox equationspresented to a freshman list of reactions thatwould go stoichiometric- you would find veryfew, if any, on such a from doing a few ally in the way presentedand yet the impressiongained by the freshmen things are.I think in our ownwork we tend to exercises like this isthat this is the way Law is ideal, forget this. Most of theequations we balance areideal, just like Boyle's teach equation balancing.I know that in and we forget thefunction of ideality when we equation for every one ofthese lists of redox equationsthat I have seen there is an dichromate ion and youhave all balanced this ahundred times oxidizing sulfite ion with twice in and then corrected150,000 students who forgetthat the chromium appears It. is a wonderfulexercise because it has a dichromate and can'tbalance the equation. sulfate is not gimmick with which you canfool a student on a quizand so on. However, that reaction as thebooks say.In fact you canadjust the conditions the only product of probably very few students so that half thesulfur ends up as S206=--another fact which schools even knowabout--they probablydon't even know of the in any of our graduate chemistry existence of S206= --a verystable, well behaved ion.Again the descriptive and often misinformative.It is certainlyidealized and I we do isalready very selective things to think in our teaching weoften miss the boat in notshowing how we idealize achieve simplicity ofthought and explanation. problem sets thatillustrate chemical nomencla- I have seen atleast three texts and compounds but by using the ture of the oxy-ionsand oxy-acids by notusing the chlorine instead. This is just tobe different from otherstandard texts, to bromine compounds that use bromine, we show we don't have to copythe other fellow.In all these books (BrOC) which have neverbeen made, never beenobserved. One find perbromate ions examples to teach with, we might regret that inchemistry, where we have somany real doesn't exist for afundamental discussion.I don't think this is select a compound that of us would bad. Perbromate ion is aconcept which we canimagine existing, and none should do the reactionsthat are necessary toform it.I don't be surprised if someone paradoxical that we find in teachingnomenclature. But I find it think it is bad to use it nonexistent while the field weteach is ourselves selecting forexamples things that are can't possibly impart evena small fractionof them to so full ofexisting facts that we chemistry to the beginning our students.How important then, arethe facts of descriptive and terminal student? laboratory work? Why are we sounhappy with We now come tothe point: Why do much about changing ourlaboratory programs?I have first it? Why are we talking so uninformative as to whatis being done atIllinois.I to explain why thistalk will be so what is being done in have been at Illinoisonly six months andI'm still learning about the end of this reportis a brief outlineof the experiments undergraduate teaching. At tentative outline of the core that are being used in thefreshman course, and a very curriculum courses beingplanned for the secondand third year.

21 I think a very significant point should be made here. That is, that the earlydiscus- sions of a possible core curriculum laboratory program in which traditionalintradepart- mental boundaries were removed began well before publicizing of the Hammondcurricular reform began.It often happens in science that when a discovery is ready tobe made, several scientists are apt to make it virtually simultaneously andindependently.I feel that the parallel and independent thinking of our core curriculum committee menand the Hammond curriculum reorganizers at Cal Tech represents just such a commondiscovery of an educational nature. The quick uptake by so many of uswho follow the leaders, (with what I hope is a discriminating eye), is further indication that theseideas constitute an important new track for chemical education. Our planning for a core laboratory at Illinois is not yet to thepoint of developing any experiments as elegant as Harry Gray's, but the pattern is the same.Laboratory work is to be divorced from traditional course work. Experimentsemphasizing techniques are to be the heart of the core program. Laboratory work as aninvestigative process is to be emphasized as the reason for doing it.At the end of the core curriculum hopefully, a student will have learned modern laboratory techniques and alsolearned the raison d' etre of laboratory work. He will then be ready for specializedtraining in a particular field and introduction to research problems. Basically it is an attitude that Harry Gray and our corecommittee are both trying to sell.I hope you won't let the fact that Harry works with twoAP-5 students and all the resources of Cal Tech obscure theimportance of the attitude. Most of you cannot match the equipment or the supervision Professor Graydescribes, but you can match the attitude and develop investigative experiments tofit your situation.. I have found the investigative attitude extremelystimulating to students in any form of work with aqueous solutions.In qualitative analysis labs students are urged tobe prepared to discover new facts (or old ones that areextinct). Examples of discoveries my students have made areformation of white AgNH3I when conc. ammonia is added to yellow AgI (recorded in Mellor's old treatise onInorganic Chemistry) and a polymeric [Cr(III) ]m (011-)n which precipitates sulfate ion(new). Many of you are familiar with my evolvingexperiment on[Cu++(NH3)4H20 ] SO4'. Students prepare it, analyze for NH3acidimetrically and for Cu iodometrically on the same sample. Theyheat the material and try to discover formulas ofvarious Cu(NH3)riSO4 species. Last fall a whole lab sectiondiscovered a new titration which should prove useful for Cu++ in the presence of otheroxidizing agents. Feeling unsure of the starch - I3- endpoint, students added 5203= until CuIdissolved quite sharply. The mole ratio of "excess" S203= to CuI was 2:1.It is a variation of the old "hypo" reaction fordissolv- ing AgBr in fixing film. The studentshad discovered a reaction which I've not yet found in the literature. A word of warning is importanthere. Using an investigative experiment in a large class where supervision is inthe hands of teaching assistants is not so easy as in a small school where the professor runsthe lab. Often new teaching assistants have never conducted aninvestigation themselves and they may be worseabout asking what to look for than thestudents. With 1,200 students investigatingCu(NH3)xSO4 (H20)y last fall, the Cu/NH3 moleratios became remarkably constant for thelast 500 reports. The habits of memorizingand regurgitating, of finding predestined answers,drilled in by previously employed educationaltechniques are very difficult to transform into habitsof

22 thinking through a problem, analyzingdata, and simply seeking and finding new things for oneself. You must be careful not topenalize the student who really seeks his own information and does not get the prettyidealized answers of the dry labbers.I firmly believe, though, that a good technique ofteaching should be used, not avoided, just because many students are passive rather thaninquisitive. Laboratory work can be interesting and wellmotivated if it is not just a demonstration of principles learned elsewhere.Qual has usually been successful because it offers the student a chance to investigate, to reasonfrom what he sees and draw conclusions on his own. We musthave experiments, not exercises, in our labs. Laboratorywork is tedious. Information comes slowly from laboratoryeffort. There must be the possibility of learning something interesting, or of solving anintriguing problem if the student is to be enthusiastic and if we are to be able tojustify the imposition of such a slow learning process on his already toobusy schedule.

First Year Majors Laboratory University of Illinois

First Semester Second Semester Weighing and glass working Preparation and analysis of Syntheses BaC12.2H20 K3Fe(C204)3 H2O - Los: of weight NaHCO3 - Fajans Ba++- bydifference Sn Sn02 for combining weight Spectrophotometric Analysis Filtering Gravimetric analysis Spectronic 2 0 NaHCO3 -) CO2 gasometric analysis Ki for HI03 Vapor pressure - Solvent and Solution Iodometric analyses. Ksp for Cd(I03)2 Acid-Base Titrations Soda Ash Freezing Point Qualitative Analysis Calorimetry Ionic Equilibria H202 4. I- kinetics Magnetic Susceptibilities (1st time this term). Include temperature dependence Distribution equilibrium Benzoic acid dimer # 2 COOH (aq) in benzene

23 PROPOSED COURSE OUTLINES FORCORE CURRICULUM LABORATORY Sophomore and 1/2 junior Years conf., 1 lab. I - CHEMICAL SYNTHESIS AND STRUCTUREDETERMINATION - 1 semester, 1 A - Properties of Matter isolation, purification, and characterizationof compounds; the determinationof characteristic physical properties. expts. one org. and inorg., eg;isolation of natural product: 3-4weeks. techniques: simple weighing andvolume measurements,determination of mp and bp; recrystallization,distillation, sublimation, column andthin layer chromatography, extraction, drying agents,solubility relationships, heating,identification by comparison. B - Reactions and Structure a) simple synthesis; goals ofsynthesis, control and directionof chemical reactions; prepare, purify andcharacterize a solid and a liquid. expts., 2-3 weeks. b) multistep synthesis; qual. useof spectroscopy and othertechniques for following reactions. 2 expts. , 4-5 weeks. C - Qualitative StructureDetermination use of characteristicreactions and spectral propertiesin identification of 2-3 unknowns from a limited list ofpossibilities; deductive logic andchemistry. expts.,4-5 weeks. 1 conf. ,1 lab. II - DYNAMICS, STRUCTURE ANDPHYSICAL METHODS - 1 semester, A - Non SpectroscopicMethods; Quantitative Work; ErrorAnalysis following the course of a reactionby titration; kinetics and rate measurements; mass action law;electrochemical properties. 2-3 expts. , 2-3 weeks. techniques: quantitative weightand volume work; quantitativetransfers; titration technique; measurementof electrochemical properties. B - An Introduction toElectronic Measurement use of amplifiers,oscilloscopes, choppers, phasesensitive detectors, optical spectroscopy; opticalscanning for kinetics, timedependence of spectra. 1-2 expts., 1-2 weeks.

24 C - SpectroscopicMethods states, transitions; general spectroscopicbehavior, review quantum Beer's Law. a) reaction rates andcatalysis; electronicspectroscopy; quantitative measurement; 1 expt. , eg: catalysisof oxidation ofa+3 by Ag+ followed by uv-vis; 1 week. b) rates and equilibria;concept of the energyof activation; temperature effects on rates; 1 expt., NMR measurement;rotation in amides,2 weeks. products, relation of c) kinetic vs thermodynamiccontrol; two diff. structure to rates; useof concept of Eact;spectroscopic analysis. 1 expt. , 2 weeks. D - Equilibria d) relationship of K andtemperature; determinationof enthalpy and entropy; follow areaction by IR; 1 expt. , 2 weeks. e) relation of structure toequilibria; approachequilibrium from each side; determination K and k1,k_1; follow spectrally. 1 expt., 2 weeks. III - CHEMICAL FUNDAMENTALS 1 semester, 1 conf. ,2 labs. A - MacroscopicProperties, Thermodynamics, equilibria, calorimetry,enthalpy (one expt. measur- experiments covering: dependence, ing all these wouldbe very neat), E.M.F.measurements, T and response tochanges in T, P, V, andother free energy, equilibrium be external stimuli, anddiffusion processes orosmotic pressure would covered, activitycoefficients. Quantum B - MolecularStructure and MicroscopicProperties, Statistics, Mechanics, Atomic andMolecular Absorptionand Emission,Scattering Processes atomic absorption andemission spectroscopy, Laboratory work using: development of the partition vib .-rot. of HC1and CD1, temp-dependence experimentally to polyatomicsand concept offunctional function, extension coupling, and concept of groups, magneticresonance,relaxation, spin- spin shift (computeranalysis), electronicmolecular spectroscopy the chemical diagonalization), dipole moment,tempera- (Huckel m.o. conceptand computer ture dependence(CH2C1-CH2C1) and lightscattering.

25 00-

THE GENERAL CHEMISTRYLABORATORY: AN EXPERIMENTALAPPROACH Jerry A. Bell University of California Riverside, California I'd like to subtitle this talk,"The Opportunity to MakeMistakes." There are too few chances left for college students toexperiment and make errors withoutbeing penalized, usually by the loss of grade points. For some,the laboratory portion of a generalchemistry course can offer this opportunity. I agree with ProfessorSienko who said in his talk to thisconference that there was no question that thegeneral chemistry laboratory was a necessarypart of the introductory course. The laboratory is,(or should be) one of the first honestlooks a student gets at science.(Thus far my remarks have mostly beenappropriate to the students that plan a science-based career; for others,lecture experiments, about which afew remarks will be made later, are probably morevaluable.) To indicate how I have tried toput these ideas into practice,I would like to describe in moderate detail the laboratory programI use at UCR for an honorsgeneral chemistry course, Chemistry 4.The students are advised to take or notto take this course on the basis of a "chemistry" placementexamination that is really a mathematicsexamination disguised as chemistry. Successin seeing through this cover, aswell as in solving the algebraic problems posed, meansthat the student will have a goodchance of success in the mathematically orientedChemistry 4 course. The course meetsin three lecture sessions and two three-hourlaboratory sessions a week. Thelaboratory sections are held to fewer than twentystudents, about fifteen if possible.(A number of the ideas introduced in Chemistry 4 have been adaptedand adopted for the more conventionalChemistry 1 which meets in only one three-hourlaboratory session a week. Thus,these ideas, while not wholly applicable to the moreconventional courses, can beusefully adapted.) The laboratory experience isused both to reinforce lecture materialand to present new concepts and information,in particular, descriptivechemistry. In order to see how the laboratory sequence fits into the course,I shall outline the sequence oflecture topics: Stoichiometry, Gases and Temperature,Thermochemistry, Second Law, Equilibria,Electro- chemistry, Atoms and Molecules,Chemical Properties, and Kinetics. The laboratory sequence(with a few comments on the experiments) is asfollows: The first experiment is thegravimetric determination of chloride in achromium chloride hydrate. (Almost all the experiments arequantitative and involve precise weighings sosingle pan balances are a necessity tomake such a program feasible,unless the students are to spend all their time in frontof a balance. Each sample astudent gets should have some meaning for him, aside from a numberin the instructor's gradebook. Hisobject in the first experiment is to get resultsaccurate and precise enough todetermine the empirical formula of the salt by analyzing only one ofthe three components.) Next the studentssynthesize and analyze (Coen2C12) Cl.(The analysis is done by ion exchange. A stock solution of(Coen2C12) Cl is made up for the analysis;the solution is initially a deep green but by thenext day has changed to maroon.Later the students get a chance to study the kineticsof the transformation as well as otherrelated analyses that lead to at least apartial answer as to what is goingon.) calor- Thermoohemical measurements arecarried out ice calorimetricallyor by adiabatic HC1 and Mg0 HC1 reactions.(The ice calorimeteris made an option imetry on the Mg 4. is lost in wonder atthe principles since often thepedagogical impact of the thermochemistry Indirect calorimetric measurementsbased on the temperaturedependence of the calorimeter.) in diphenylamine. of equilibria arealso carried out for a solubilitysystem, naphthalene isoteniscopic determinationof vapor pressure or a few students takethe option of doing an system.) study of theaniline-sulphur dioxide system. Thelatter study requires a vacuum acid- Equilibria, especially ionicequilibria, are further studiedin the systems propionic solubility in acidic solutions,and bromcresol green water- carbontetrachloride, Ca (103)2 gained, electro- (Bjerrum method) as afunction of ionic strength. Withthe background now readily carried out andinterpreted. After someexperience making chemical experiments are experiment is done inwhich the in- cell measurements on someconventional cells, a class equilibrium constant measurements onthe silver ion-hydroquinonereaction structors carry out the data and do the data both analyticallyand electrochemically;(the students take down This is the first of thelecture experiments inwhich the students analysis for themselves. themselves.) participate intellectuallybut do not carry out theactual manipulations into the fundamental At this point we areready to study atoms andmolecules but we run experiments are hard to interpretand easily interpretableexperiments difficulty that easy has been to introduce a are usually verydifficult or expensive to carryout. My answer experiments. First we takethe temperatureof the sun, which isassumed number of lecture interpretation gives body.(This dramatizes Planck'scontribution and the to be a black non-straightforward equipment.It has also some experiencein calibrating somewhat and, to use the campus afforded a number ofinterested students theopportunity to learn how computer facilities fortheir data reduction.) of the basis Further studies involvemodel building anddiscussion in the laboratory studies. A very subtlestructural effect, optical for the models in termsof spectroscopic and resolve rotation, is introduced by anexperiment in whichthe students synthesize (Coen3) 13 into its opticalisomers. properties on chemicalinteractions is indicated in astudy of The effect of structural (Again this is a lectureexperiment in which the the acetone chloroformsystem by NMR. the and operated bythe instructors andthe data are given to instrumentation is explained experiment are presentedin.Chem. student after the demonstration.The data and the of this experimentis to introduce NMR tostu- Ed., 44, 200(1967). A secondary purpose organic chem- dents who will find it used again,almost immediately,if they take VCR's istry course.) they desire in the At this stage, four weeks areallowed to thestudents to do anything another experimentfrom the text, Bell, laboratory; go further with anexperiment, do difficulties with an (Addison-Wesley,1967), examine the Chemical Principles in Practice (This part of the program,inaugurated experiment, or develop anentirely new experiment. work at his own level this year, seems to havebeen a success inallowing each student to and pace on somethingthat interestshim.)

27 Penultimate ly the students do two kinetics experiments: aninvestigation of the Coen2C12+ transformation and either the iodination of cyclohexanone or the enzyme catalyzed inversion of sucrose.(The cyclohexanone reaction can be used to introduce kinetic isotope effects, their effect on rates and themechanistic information derivable therefrom. The enzyme reaction introduces the students to thecomplexities of bio- chemical systems and is particularly valuable for thosestudents who will not take any further courses in this area.) So far, you see, almost everything we havedone is quantitative, but qualitative work, especially order-or-magnitude, reasoning,is stressed throughout also.(Many tests of ideas and test-tube experiments aresuggested and are carried out by the students or instructors.) To further emphasize thenecessity for qualitative tests, chemical observation, and deductive reasoning, we do, atthe end of each quarter, a final problem.(Nine numbered test tubes containing nine solutions are given toeach student. The problem is to match the numberswith the list of solutions without using any external reagents.This problem is extremely popular and generates alarge amount of enthusiasm as well as reinforcingand introducing a great deal ofchemistry.) We hope that the ways of attackingproblems and thinking them through that we have tried to develop will enable thestudents to finish successfully the final problem with a real sense of accomplishment, andwill start them with a boost along their path toward an education in all areas, notsimply chemistry.

28 THE "INTEGRATED"LABORATORY Harry B. Gray California Institute of Technology Pasadena, California

We would all agree that somework needs to be done inthe laboratory program in chemistry. However, it is not my purposeto criticize the presentlaboratory at all.In- devote most of my remarks tothe plans some of us havefor a stead, I think that I will laboratory"; I use it new laboratoryin chemistry. We haven'tused the term "integrated now because it wassuggested to me as the title forthis opening talk.(I suppose that integrated laboratory -- wehave stayed away fromthis term because one could call it laboratory, I we are not surewhat we are integrating.)The problem with the first-year think, is that we are constantlyattempting to correlate theexperiments in the lab with something that is going on in thelecture, and this correlation,which is forced, has led experiments and short-rangegoals.I believe that instead weshould us into fairly petty design a try to correlate the laboratorywith the laboratory.In the long run, that is, to laboratory covering a three-yearperiod which steadilybuilds up the student's proficiency and methods and finally getshim to a point after three yearsthat in laboratory techniques this he is able to design and executereal experiments. And sofor the purpose of opening conference, my collaboratorsand I have drafted a resolutionwhich does not have to be adopted by this conferencebut will certainly be adoptedby me as a guiding theme. The central purpose of the newlaboratory in chemistry is toteach students how to design and execute real experiments.The program should encouragethe student's curiosity and develop hisability to observe precisely, aswell as his power to apply pre- It must stimulate hisimagination with experiments thathe vious experience critically. of funda- can recognize asworthwhile and simultaneouslyinsure a thorough exploration mental techniques used inmodern chemical research. I will have to give youtwo versions of what'sgoing on. One version is due to Michael Smith of Cal Tech, andmyself, and George Hammond,Charles Wilcox of Cornell, will probably happen at CalTech next year.(Actually, the the other version is what subject is that people at reason I amgrateful to accept all invitationsto speak on this Cal Tech regard me as asuspicious character; naturally,I am pushing this program at any listen.) Here is the situation as itstands now. The lecture pro- place where anyone will now gram has to someextent forced this overallrevision of our laboratory program; we are attempting to put in athree-year new curriculum inchemistry -- the first course being the second course beingStructural Chemistry (a sophomore General Chemistry and work yourself up to a course), and the third course beingChemical Dynamics. Before you Dynamics," we will simply saythat it has to point of frustration overthis term "Chemical then, there is an do with all mattersinvolving reactions andreactivity. And if you like, attempt in this program torealign chemistry along theseborders of research today and to fuse together organic,inorganic, physical, andanalytical cheRistry in this sequence. Now, so much for thelecture part of it.The laboratory program whichis being designed does not necessarilyhave to go with this sequence.In-fact it may very rightfully

*Charles Wilcox and George S.Hammond

29 stand on its own. As a matter of fact it may be the only partof the program which has any sort of acceptance at all, and it is not newbecause too many places around the country have been playing with the idea of alonger range, better correlated laboratory program. We are certainly not thefirst people to suggest this strategy. In the new laboratory, as we see it now,the first two years will be rather closely linked and will be devoted to learning techniquesand methods of doing experiments. In fact there will be a clear-cut divisionof the first two years of the experimentalwork; a large hunk of the laboratorywill be devoted just to experimentaltechniques and methods for doing various types of measurements, and asecond, probably larger, hunk will involve application of the techniques and methods to a ratherlong-range correlated experimental program which I call"experimental sequences." Chemical systemsfor the experimental sequences are chosen for theirrichness in reactivity and structuralbehavior. The first year of the program has to besuitable for a general chemistry course.Thus, one would do the partswhich make up general chemistry -- chemicalsynthesis, chemical structures and chemical dynamics. Thesewill be looked at in the experimental sequences which will become available for the first year program.This will rid us of that awful formula (one lab day) = (one experiment). Wefeel that the short-range approach so badly stifles chemistry that students do not have thechance at all to find out what chemists actually do.In the specific program I am going tooutline, a third of the course will be devoted to learning techniques and methods andthe last two-thirds of the course will be one or two "big experiments." There will be only one experiment in theentire year if you like. Now, in the second year, essentiallythe same types of techniques will beinvolved, or the selection willbe from the same group of techniques. Again,there is emphasis not on designing your ownexperiment, building your own equipment, but onusing equipment and techniques that are readily accessible.The experiments are fairly carefully planned out, but the emphasis here willbe on physical and chemical methods for thestudy of structure. These may take the form of classical"proof" of structure of an unknown material, a kind of experimentthat most students especially enjoy, or theexperiments may be designed to extract special informationconcerning substances of known gross structure. Measurement of dipole momentswould be an example of the latter type of work. In particular, spectroscopy will be brought inheavily during the second year sequence. The sophistication, since all three years arerather closely correlated, builds up in the second year but one is still doingblack box experiments. The courses are built more around discussion of the actualexperiments that are going on and the results that come out. The third year parallels thelecture discussion of chemical dynamics.It is in this year that we allowthe student to design and execute his ownexperiment; and the design and execution of an experiment mayinvolve actually building some new apparatus orsub- stantially modifying some available apparatus.We hope to also teach students an appreciation of the chemical aspectsof engineering experiments, for example, wisechoice of reaction conditions to make a ratemeasurement convenient and meaningful. Again,the experiments that will be available onthis level are ones that have been carried out some- where before. I should now like to outline anexperimental sequence which we feel integrates a large amount of chemistry. The sequenceis designed to increase the student'sconfidence in the techniques I have mentioned previously:all these techniques are involved in this one experimental sequence. The experimental sequencewould be in the first year, but with emphasis on the structural aspects it would be ideal for the second year. We have two students in Chemistry 2 class testing the experimental sequence thatY am going to tell you about. Proposed First Year Program I will designate a 3-hour lab as one lab unit - thus we have2 units a week. We start withquantitative analysis; gravimetric analysis first, following Waser's lab at Cal Tech. One gravimetric experiment takes 5 units, introduction to volumetric techniques and a volumetric gas analysis takes 3 units, and the wet analysis takes 6 units.For the wet volumetric analysis the student can do a redox titration, or anacid-base titration, or any one of a number of quantitative volumetricexperiments.Later the student will return to all of these techniques in the course of an experimental sequence.Thus he does nothing in the first part of the lab that he does not need later; there is adefinite attempt to correlate the entire program. The first part of the programrequires 14 units and so the first quarter is spent developing the very basic techniques of quantitativeanalysis. This will not be a research project 2sj: se, yet it is a research type operationbecause the experiments will offer possibilities of great rewards. Therewill be some modifica- tions involving experimental design so that the student canactually do a good experiment himself during the course of the year. At the end of the three-year program,the student should be able to move smoothly into a true research program. The techniques that we feel should be mastered in the first two yearsof the program integrate the large amount of traditional chemistry as it now stands.In approximate order, these are as follows: 1. Quantitative analytical methods, including gravimetric analysis, volumetric analysis, both liquid and gas. 2. Separation of mixtures which will include development of techniquesof distillation, sublimation, recrystallization, chromatography, and so on. 3. Development of methods to determine molecular weights; freezing point depression, boiling point elevation, osmotic pressure, etc. 4. Electrochemical methods. 5. Spectroscopy, including visible, ultraviolet, and infrared. 6. Magnetic susceptibility and magnetic resonance methods. There are others, but these are the six areas that wehope will be covered in the first two years of the program.In the third year, the student would be exposed to glassblowing, machine shop work, electronics, and so on. Hewill be expected to put together his own experiment. An experiment in the third year mightbe to study reactions in a student-built shock tube. Now, how much time each year for this program? For the first year,three hours per week in the lab, one lecture (or recitation if youlike)a week for the laboratory. For the second year, six hours per week in thelab, one recitation; third year, six hours per week in the lab and one recitation. This summarizes the program that Hammond, Wilcox,and I are proposing.I must say that I personally prefer six hours per week, and I think that if wedesign a laboratory which is sufficiently exciting and sound, the students are going to respond and say,

31 "We want this laboratory and you can'tlimit us to only three hours a week:". Thisis certainly the initial reaction we are getting from somestudents in our new course, Chemistry 2.Student apathy over the country is simply becausethe labs, they feel, have not reached out enough and have not stimulatedthem.I think the reaction will be veryfavor- able to a lab which is really a teaching lab and putschemistry in a very exciting framework for students. Unfortunately, I can't tell you verymuch about the second year of the new program, and Icertainly can't tell you anything about thethird year at this early date. I am personally involved at Cal Techin the first year lab.In Chemistry 2, we are testing experiments and next year we plan a largerscale operation. Second Two Quarters The experiment is called the synthesis,characterization, structure, and reactions of metal acetylacetonates. You might expect me to comein with some coordination chemistry experiments, and I am living upto this expectation.I offer no apologies for it, because I hope to show that this typeof experiment does integrate ideas fromstructure and reactions in both organic and inorganicchemistry, in a way that we feel is really successful. The first step is the synthesis oftrisacetylacetonatochromium(III). We start with an aqueous solution of chromicchloride and add acetylacetone. The reactioninvolves substitution in an octahedral complex and so you startteaching ideas of reactivity in such systems. This synthesis is carried out byhydrolyzing urea in the solution.It is a fairly interesting synthesis.It shows students how youtrick things into going properly. The urea hydrolyzes to give ammonia and CO2 comesoff. As the ammonia is liberated, thesolu- tion becomes a little basic andthe chromium system becomes moreversatile in substitution, opening magnificentpossibilities for talking about this in somedetail. The protons come off the acetylacetoneand are captured by the ammonia togive ammoium ions. A gas analysis of theliberated CO2 can be done at this pointif you like.Recrystallization of the trisacetylacetonatochromium(III)product is carried out until pure,red-violet crystals are obtained. The second step is thecharacterization of chromium(acac)3.The compound can be sublimed at 100° so sublimationtechniques are brought in at this point.It boils at 340°. It is a monomer in allsolvents and molecular weightdetermination by some method is done at this point. The compound is paramagnetic tothe extent of three unpaired electronsand magnetic susceptibility measurements can becarried out.If the necessary equipment is available, the paramagnetic properties mayalso be detected by observation of theeffect that the species has on N.M.R.relaxation times in solutions.It also has a very rich visible spectrum. The idea of paramagnetismand energy levels in these types ofmolecules is brought into the discussion of thisexperiment. This experiment wasdesigned so we could talk about spectroscopyand electronic energy levels, andhere is a very rich spectrum with which to do this. Atthis point the students testing thissaid, "well, we really want to examine the spectrumof acetylacetone by itself,"and eventually they did look at it and it made a lot of sense tocorrelate the acetylacetone spectrumwith the complex spectrum .

32 Chromium(acac)3 has a very easilyinterpretable infrared spectrumwhich allows introduction to molecular vibrations.You see two types of CHfrequencies in a not very complex infrared spectrum. Manypeople would want to do this inthe second year of the lab. You can brominateCr(acac)3, for example, and nitrate it,reactions which are worthwhile discussing; so one thingthat is done in this sequenceis halogen substitution. Halogen substitution in thissix-member hetero ring goes veryreadily at room temperature. The brominesubstitution product,Cr(acac-Br)3, is a dark, red-browncrystalline material. One does crystallizationsand separations, etc. , again.We emphasize the techniques involved in chemicalsynthesis at this point. You can seethat the magnetic substitution out on the edge of thecomplex -- the environ- moment does not change with interest- ment aroundchromium(III) has not been grosslyaffected. However, some fairly ing changes take place in theelectronic spectrum and the infraredspectrum drops out of 1520 one of the CHbands, leaving only one CH band.Cr(acac)3 has bands at 1560 and cm-1, and Cr(acac-Br)3 has a single band at1540 cm-1. You can go backthen and think about this problem, and thinkabout the detailed assignmentsof this spectrum, but here it's again open for the students.The halogen substitution is thething that is done and there is a choice of determinationof molecular weight, or analysisfor bromine or chromium. What you want to dohere is optional in this sequence,but all of the possibilities The only are presented tothe student. He developshis own pattern of working through. thing that he has to presentis evidence at the end of the yearthat he has covered the techniques that we have outlined tobe covered; at the end of the yearhe writes up the entire experiment, what hehas learned, and so on. The choice of nitro substitutionis presented to him, continuingwith the organic type reactions in this sequence. Nitrosubstitution can be done fairlyreadily with acetic anhydride and copper nitrate.It does not go in theabsence of cupric ion very readily at all and so one can talk aboutreaction mechanisms andhomogeneous catalysis. The complex which is the finalproduct is the nitrated pseudo-aromaticring system -- feeling you see now we arebuilding up larger and largermolecules, and a student has the that at this point he is reallydoing chemical synthesis. Hedoesn't dread doing the analysis at this point -- he really wantsto do it, we found out --but one thing we did do, I found out, is slightlyunderestimate the time required foreach step for just making the stuff.I had down two periods -- ittook about seven! There is a presence factor inthe lab and that, I think, iswhat we are trying to teach. Students have to fool around withrecrystallizing. learning to work withthings, and working with their hands.It takes some time toet going! The infrared ofCr(acac-NO2)3 can be looked at with some profit.There is an enormous shift inthe visible-ultraviolet spectrum due to the nitrosubstituent and that can bediscussed, particularly in astructurally oriented course. Correlated Studies

For one thing you can make and measureproperties of other acetylacetonecomplexes. The cobalt(III) complex is not madein the same type of synthesisbecause of some differences in substitutions atCo(III). One reason the cobaltcomplex. is of interest specific- ally is that it allows introduction tothe nuclear magnetic resonancetechnique. The Co(acac)3 complex is diamagnetic, asmeasured by the student, and we mayconclude that the three extra electrons(over Cr(III)) have paired; thus the energylevel being filled

33 in octahedral complexesin going from Cr (III) to Co(III) must have an orbital degeneracy of three. Co (acac)3 canalso be brominated and nitratedin exactly the same way as Cr (acac)3. So the "aromaticsubstitution" part of the experimentcould be done here instead of earlier. The final point is thesynthesis of copper acac. Thiscompound is made to emphasize differences in structure and tobring in one final techniquein this program, i.e., the tech- Because the copper compoundhas one unpaired elec- nique of electron spin resonance. nuclear tron, it shows thenuclear spin of Cu nicely.Furthermore, this is a square planar compound. The substitutionreactions of this compound arevastly different from the six- coordinate ones. You canmake the bromine derivativeof Cu (acac)2 and compare its re- either the chromium orcobalt complex. This copper complexis action with acac with talk about ideas of structure and much more reactive forexchange of ligands and you can reactivity. experiment, but I think you What I have described isperhaps a coordination chemistry type of experiment whichtruly integrates ideas of inorganicstructure can see that this is a much and reactivity and organicstructure and reactivity. Wehave others which are pretty the way through. Two typesof manuals are being developedfrom organic in a sequence all the other our program -- onewill teach basic techniquesand basic operations, whereas will be devoted to these mastersequences, with onemanual for each sequence. short time I have beenable to communicate some ofthe things we I hope that in this singularly poorly qualified are doing.It is in a very early stateand to some extent I am to discuss this program,but I thank you very muchfor inviting me. STRUCTURED CHEMICALEXPERIENCE IN UNDERGRADUATELABORATORIES John E. Baldwin University of Illinois Urbana, Illinois where to start whenconsidering undergraduatelaboratories or One hardly knows of possible new approachesto the teaching ofundergraduate labs. A great range approaches is available.On one hand you maylook at the basic underlyingphilosophy operation, and this veryeasily leads to Olympianconsiderations; behind the laboratory experiments, what you on the otherhand you may talk aboutthe nitty-gritty of particular should do first, next,and so on.Let me attempt to makeclear this Olympian view example. A few weeks agothe newspapers carried reports on afive- through a specific United States year internationalstudy of education andperformance in mathematics. The eighth among the countriestested, behind Japan,Belgium, The Netherlands, came out experiment. England, Scotland,Australia, and France; Russiadid not participate in the why the U.S. ranked sofar behind the leaders werephrased in this The conclusions as to real pressure Olympian vein: "Thereis little doubt that inJapan where youth is under very school or fail miserably inthe highly competitive economy,mathematics to succeed in of the affluent assumes greatimportance.In the U.S. andSweden, perfect examples society, there is little pressureto take the tough anddemanding courses." And again, suggested that the Japanesedevotion to order, characteristicof the "It has also been Perhaps most entire social complexembedded in Confucianism,is akin to mathematics. plays a significant partin the total culture; thechildren are intro- important, mathematics things may be true but may notbe of duced to numbers at anearly age at home." These to devise better waysof teaching mathematics.Similar much help when one attempts and per- approaches will not be ofmuch immediate help indeciding how we can change It may be that thebasic difficulty holding usback in haps improve organiclaboratories. character, or our organic laboratories has todo with some culturalflaw in the American governmental policies in some areaof the globe, or thefact that graduate students are aren't working as hard asgraduate students did when we were being paid too much and approach I intend in graduate school. Wemight discuss thesethings, but that is not the is based at thesingle experiment level.A good example of to take. Another extreme Organic Chemistry' this is the question:"Why doesn't thisexperiment in 'Experimental questions at a latertime and I will be glad totry to answer work?" You can raise such should go about them. But I prefer now tospend the availabletime discussing how one how one should goabout structuring organic planning for an organiclaboratory experience, for the people tak- laboratories so that theywill provide ameaningful learning experience bluntly my ownprejudices, not that I thinkthis ing the course. As I goI'll state pretty have something quite may convince you orthat you'll be won over,but so that you may concrete to attack in thediscussion period. only answer that reallysticks in a student's mindis the John Holt has said the If this is so, then onehas to answer to a questionthat he asks ormight ask of himself. any laboratory sothat the students are led go about structuringthe organic laboratory or their questions, and they'll to ask questionswhich become importantto them. They are be solved. What sort of experiments can be done that will lead to the greatest pleasure for the students and will involve the least possible instruction, interference, and correction by the teacher? Perhaps another question we should raise is, "Do we really believe in the importance of experiments over theory in chemistry, or are we going to make our labs nothing more than devices for packing in the recipes faster?"I think that chemistry really is fundamentally experimental in nature; I think you can teach chemistry through experimentation. To do this the experiments have to be efficient, up-to-date, and attractive; through the experiments the students are going to learn chemistry. They're also going to experience a certain excitement and involvement; they'll develop the mental and manual skills needed for further work, if the structure is properly prepared. The first specific question that comes along when you come to structuring an organic course is, "For whom will the course be taught?" How you answer this question will greatly influence what you put in the course.Let me give some statistics on undergraduate enrollment at Illinois last fall to emphasize this point.In the freshman courses we had some 2000 students.In the first semester organic courses last fall we had 550.In the second semester organic laboratory course, the enrollment was down to 70, and in the last semester of organic laboratory given, the enrollment was 7.It is clear that if we are teaching our courses only for the chemistry majors who are going on to become professional organic chemists, we're teaching the first semester of organic laboratory for something on the order of one percent of the students. And if we structure the course with only these students in mind, we may seriously short-change some ninety-nine percent of the students, even if the course in the catalog is designated "for non-majors." Let me give some quotes to bring out the seriousness of this problem. This is something often really neglected when we actually get down to the business of planning the courses. The first quote is taken from a report of a major university in this country concerning their plans for new laboratories. "Our second year course would have non-majors enrolled.It would be better to adapt the sophomore courses to handle this service load. rather than to teach non-chemists. This service load will place limitations on optional experiments." This comes from a noted educator: "The work that the schoolmaster is doing is inestimable in its consequences. He is laying the foundation of the careers of men who are to lead the next generation. He is also knocking all the best stuff out of a great number of them." This is not an exaggeration. We tend all too often, I feel, to teach the courses concentrating only on the successful one percent of the students and being fairly hard-boiled about the failures.I think we need to really consider this very carefully when we're deciding for whom courses will be taught. The next question is, "What is the course going to be about; what will we attempt to achieve in the course ?" Here there are really two highly polarized views; they may be expressed with the following two quotes from curriculum reports of major universities. "The central purpose of laboratory instruction is to teach students how to design and execute experiments. The experiments should increase his power to apply previous experience critically."Contrast this view with the following alternative position. "The main emphasis is to be on practical lab operations and not illustrations of chemical principles: i.e., to train students to work with their hands and to work with simple lab apparatus. The fare should be based on thoroughly tested recipes." What about content? What sort of experiments should be put into a course? One can generate the content initially by making a list of the various techniques that should be covered; in organic this would include recrystallization, distillation, chromatography of various sorts, perhaps a sealed tube reaction, etc.Next, one would need a list of the chemistry to be taught or illustrated, such as thedifference between kinetic and thermodynamic control, determining the order of a reaction in akinetic experiment, structural elucidations, multi-step syntheses, etc. Then onewould have to list the limitations dictated by experience and the currently availableinstitutional facilities. And these limitations are very real matters of time,equipment, money, space, student attitude, and staff attitude.By combining these three elements--techniques,chemical principles, and limitations--one can make the necessarycombinations and accommoda- tions and come up with a list of experiments. Now, inworking out this compromise one may need some guide lines goingbeyond the limitations of time, equipment, and soforth. I would suggest a number of criteria for matchingtechniques with principles and limitations. The first and really most important is to do whatexperiments you do well, as well as they can be done. This meansoperating withoutujerry-rigged"equipment and foregoing 15-minute distillations through columns having 1.1 theoreticalplates and calling the exercise fractional distillation.If there are no funds to acquire what would be regardedin a good academic or industrial lab as adequateinstrumentation or equipment, don't do experiments which require them.It's better to do other experiments with simpler and cheap- er apparatus, and to do themwell. Another criterion suggested has to do with choosing theexamples:I don't think it is wise or possible to try to choose examplesthat will cover the gamut of synthetic reactions in organic chemistry. Experience inlearning is not at all a linear thing.Stu- dents have their point of real take-off atdifferent times; shortening this time or this in- duction period should be what we are aiming for. Onemust try in the initial experiments to help the students develop up to theirtake-off point, where they are ready to work quite independently, to do for instance a type of reaction they have nevercarried out before because their expriments earlier have accustomedthem to think for themselves and given them the freedom to think for themselves.Experience isn't linear, so don't select experiments as though it were. Chooseexperiments that you think will contribute most to helping the students achieve this self-sufficiencyand confidence in brand-new situations. I think it's important to selectexperiments having a wide range of difficulty and of possible outcomes.If all the experiments result in either success orfailure, the outcome will be many dissatisfied, discouragedstudents going through the course having an un- satisfactory, negative experience.If experiments can result in a varietyof outcomes ranging from perfect success through manyintermediate levels down to complete failure, students will have much more freedom forlearning and improving their performances. The laboratory should tie in with thelecture material closely.If they do,they can reinforce one another.If they are taught as separateentities,quite often the overlap will be so small that it will simply serve toconfuse the students.In a number of schools the practice is now developing of delaying startingthe organic laboratory until the second semester or quarter.I know of no justification for thisother than justifications based on expediency. After the first term abouttwo-thirds of the people drop out, and then the survivors can be given a laboratory experience.It may be that the two-thirds of the people lost in the first term would have gotten intothe subject matter much more directly through laboratory experience that wouldmake the lecture material comprehensible or provide some stimulation for learning thetheoretical background.It may be that their whole attitude toward chemistry and science maybe warped by a bad experience based on a diffuse theoreticalcontact with chemistry rather than a concrete,enjoyable laboratory experience.

37 Another big factor in designing the experiments for a laboratory course hinges on whether the course is to be answer-oriented or problem-oriented. Much of the push for more rigorous educational standards in this country in the last ten years(since Sputnik) has been entirely answer-oriented. The drive for higher standards has always been in terms of more right answers per unit time. Students can be kept so busy getting right answers that they have no time to think. One of the youngstaff members in physics in Urbana maintains that the students are much too busy; they are in laboratories or lecture halls such a large fraction of the time that they don't have any time for study.If a student is in laboratories or lecture halls forty hours a week, when is he going to really learn something, really study through material for himself? Even a problem-structured laboratory must provide students with the freedom and time as well as the equipment necessary for seeing a problem and then going ahead toward a solution. One can't be too preoccupied with laboratory scheduling and meeting firm deadlines, or the problem- oriented lab quickly reverts to an answer-centered routine. Another difficulty in planning an organic laboratory is that it always has to be revised, and revision is work.Let me make this point explicit by commenting on a lab text I wrote a few years ago. At the time I tried to make the text as up-to-date as possible, but in going through the book now there is hardly an experiment which doesn't need revision. We now use electrically heated, air-cooled melting point baths in place of the old Thiele tubes. Mettler and Sartorius top-loading balances have replaced the slower and less accurate instruments.In our thin-layer chromatography experiments, we used microscope slides dipped in the absorbant suspended in a volatile solvent. This is still done in some research laboratories but most analytical thin-layer work is now done on precoated plates sold by Eastman and other companies. The importance of preparative thin-layer chromatography has grown to such an extent that this would have to be included in any revision. The temperature controller we described in the text for the kinetic bath is now completely obsolete. A mercury controller and relay of the sort you're all familiar with has certain disadvantages: the mercury may be spilled, the glass housing may be broken, etc. We now use a fully proportional temperature controller based on a thermister sensing element.* The VPC instrumentation picture has changed radically in the last two years. Carle now has good instruments selling for around$300, and it is possible to build a very good recorder for VPC work for around $100. I've said nothing about basic changes in experiments.Let me now mention just one example of the need for doing this. We have in our lab text a qualitative organic scheme based on sodium fusion for elemental analyses.Just a few weeks ago while correcting unknown reports in our advanced qualitative organic analysis course, I noted that the students did very well on their general unknowns but poorly on elemental analyses. They had trouble recognizing Prussian Blue and with the fluoride test.In class I attempted to place these results in some perspective by emphasizing that sodium fusions are now used only rarely in research applications. Other methods, such as mass spectrometry, are available. After class I tried to remember the last time I had run a sodium fusion in my research work, or how long it has been since any student in my research group had run a sodium fusion, or the time since I had seen a sodium fusion reported in a research paper.

*R. Anderson, J. Chem. Ed.. ,in press.

38 It's been a long time. Why are we teaching studentsto run sodium fusions?It's traditional. Might there not be betteruses for the time now spent on these fusions ? What about incentives? Why should a student walk into the organic laboratory and work hard, with great curiosity and drive? Thesame problem concerning incentives comes up in any educational setting. On the University of Illinois campus there has been,over the last two or three years, an experimental pre-schoolprogram. Some of you may have read about this Bereiter-Englemann project in a recent issue of Harper's.* Thesemen have developed an intensive academically oriented educational program for three and four',ear old kids from culturally disadvantaged backgrounds. The children in thecourse of the : two-and-a-quarter hour session each day have three twenty-minute periods of work. One staff member and six children exchange questions and answers ina very intense atmosphere.It is not unusual for the teacher to get off over 200 questions in thecourse of this twenty-minute period and for the children to answer these questions in full sentences. When the experiment first started they had some trouble: the children weren't terribly anxious to participate. The teacher would ask a question and the children wouldn'tre- spond. After some trial and error the staff evolved the effective technique of distributing raisins for right answers. Some of the children had iron deficiencies and so the practice could be justified.For the first six weeks of the course they used these raisins for rewarding the children and were pretty tough about it.If a child didn't respond or gave a wrong answer he was told, "Too bad, Johnny, you can't have a raisin, that's the wrong answer." After about six weeks the children were really good at getting raisins, and at that point they were cut off."You're big kids now, it's still important to answer the questions and learn, but no more raisins." And the performance of the children kept up at a very high level. They didn't need the raisins any more, they operated under their own steam. One of the teachers in the project had an uncertain moment in a local grocery store: she bumped into her daughter's second grade teacher and was asked, rather critically, "Is it true that you're now bribing the children with raisins?" Her embarrassed admission, "Yes, we are using raisins," was rejoined with a quick smile and the admission, "I use cookies I" Well, we can't use raisins cr cookies on college sophomores. What are we going to use? Certainly the thing we've used most in the past has been fear, or a grading system which meant fear. This doesn't work.It works only in making the students docile and unhappy and it's not going to contribute to any worthwhile, meaningful learning experience. A few years ago a student in our beginning organic lab course was supposed to make an acetate derivative of glucose and he turned in as his product sodium chloride. The identity of the white crystalline material was soon determined by the graders and appropriate steps were taken. When the student appeared before the special committee on academic discipline of the Liberal Arts College, he argued that he shouldn't be' thrown out of the course or out of school; rather he should get half-credit for the experiment because, although the purity of his preparation was poor, the yield was excellent. This is the sort of myopia we inculcate in students when we attempt to push them around con- stantly with grading systems. The students are under terrific pressure as it is. They don't need the extra pressure that comes with a rigid grading system.

*Harper's Magazine, January 1967, p.55.

39 During my first semester teachingorganic laboratories at Illinois Iobserved a student trying to recrystallizesomething from a mixed solvent system;he had selected ethanol-hexane and it wasn'tworking very well. He showed thisdiscovery to his neigh- wild laughter. He was under terrific pressureand the laughter was bor and broke out into he'd his way of releasingit. He realized that he had goofedbadly; all his life in school been operating under asystem asserting that if yougoof, you're stupid, and the grading system will get you. incentives if you discount thesuitability of a harsh grading What can one do for and give a stu- system?I think you're forced todesign experiments that are interesting dent something to show forhis work.If at the end of a preparationthe student can cap it off by running an interestingthin-layer chromatography comparisonwith authentic materials, or if after a distillationhe can put samples of hisfractions into a VPC instru- ment, or identify aproduct spectroscopically, theexperiment will provide, atleast to motivation that is a function of theproblem he is working on. Theapproval some degree, a stimulating in- or disapprovalof the instructor will becomecomparatively unimportant in experiments is difficult, but notimpossible. Students usually centive. Designing such at frequent enjoy unknowns.I encourage the use ofunknowns and laboratory examinations intervals and with the emphasis onrecognizing and solving aproblem, rather than on the grade the student may secure. Especially in the largeuniversities, knocking oneself What about staff incentive? that out for an undergraduatelaboratory is, well, it's not verysmart, it's not an activity One of these curricular statementsI mentioned earlier com- is particularly rewarded. teach mented on the fact that ithad become common practicefor junior staff members to senior people to teachthe lecture sections, and thatthis had the laboratory and for more is quite led to a lamentable lackof correspondencebetween the two. The implication clear: the lecture is importantand the laboratory isn't; it canbe entrusted to the younger time consuming, andproblematic.If you muff a lecture, so staff.It is more distasteful, There are other ways in which what?If you really fail in thelab, students can be hurt. teaching labs comes up.One instance concerned a youngstaff this prejudice against When member who was burdenedwith a gigantically heavyteaching load one semester. senior colleague about thesituation, he received the he talked with the appropriate more only the begin- assurance that his veryheavy teaching loadwould be balanced by having to teach thefollowing term. The lab course wasused as a ning organic laboratory course be taught so sop. The implication wasthe laboratory coursewasn't important, and could load. Obviously therewill not be good undergraduatelabora- that it would be a very light good lab courses tories unless the staffmembers involved andtheir colleagues really think are important. How difficult is it tochange and develop a newcourse?It's very hard, for there is all familiar with GeorgeHammond's quote about so much inertia tobe overcome. You're conservative, an attitude our conservatism:"Chemists as a grouphave become highly activity designed to pursue newknowledge."It is especially that is inappropriate in any equipment and a true, I think, for innovationsin the laboratorythat require money for new has been doing things one wayfor twenty years. And a change for the storeroom man who be re- change in the content of laboratorycourses, or achange in which courses are to quired of chemistry majors, may upsetthe status quo in a department.These are very real arguments for doing nothing,for doing things the waythey've always been done. Hammond has said that deletion ofoutdated material would be madeeasier if all existing elementary courses were erased as astarter. The opposite position,defending the current practices and course contents,stresses the potentialhazards.of change: "One does not burn down one'shouse in anticipation of a better one." Whenever we talk about course revision, courseinnovation, etc., a number of people talk about ideas. What shouldbe done with content, structure,timing? And we have a number of people talking aboutdevelopments that would require tenfaculty-man years, major problemsof resources, transitionaldevelopment through pilot projects, possible funding from outside sources,visiting staff and graduate assistantsto work out the new experiments, andestablishing workable "operatingmechanisms." "Operating mechanisms" is often a euphemism forgetting all the people who shouldbe teaching to teach the undergraduate laboratory courses.Course revision is too oftenlooked on as an enterprise or some sort of boondoggleto be done by outside experts orinside operators, an enterprise thatshouldn't interfere with the really importantthings chemistry professors may do with their timeand energies. Why is there so much inertia?People feel very stronglyabout the way they teach their courses and their own visionsof what constitutes basicmaterial. One suggested explanation for this has been offered:"Basic concepts are a veryhighly personalized matter, usually closely related tothe first things that gave a manintellectual satisfaction in his own educational experience.Teachers hate to trim their courses, notbecause they are building monumentsto themselves but becausethey have packed the courses with ideas which are trulyindispensable to themselves."If you're going to revise your course you may have togive up something trulyindispensable to you. An architect specializingin church architecture, whilelamenting oh the difficulties of dealing with churchboards observed, "It's funny,but every member of a church board has strong opinions abouthow a new church structureshould look. When you pursue these opinions it turns out thatthe new building must be justlike the church he went to as a boy."I think similar problems arereal barriers to any innovationsin our own courses.If you are using the text which youused when you were taking organicchemistry in college, or if you'reusing experiments that werereally exciting to you when you were taking organiclab five or ten or more years ago,maybe this point should be very seriously and honestly considered.Is your favorite experiment,the one that survives term after term, the bestpossible experiment, or is it onethat has a very special meaning for you? I would like to injecthere parenthetically a comment on someof the new trends and curricular changes that arebeing evolved. You know thatseveral universities, including Illinois, UCLA, MIT, andCal Tech, are considering orexperimenting with non-division- Let me give you a shortsketch of what will evolve, alized core laboratory curriculums. will be a or what I thinkwill evolve, at Illinois.Following freshman chemistry there three-semester core curriculumin laboratory practice requiredof all chemistry majors. The first semester willbe devoted to structure andsynthesis.It will involve synthetic manipulations, characterization ofproducts using spectroscopic andchemical means, and some quantitativeanalysis. The second semesterwill be concerned with dynamics, structure, and physicalmethods. Here both classical wetmethods and more modern instrumental methods will beemployed to measure kinetics ofreaction, equilibrium con- stants, etc. Finally, thethird semester will be onchemical fundamentals.It will be a fairly sophisticated physicaland instrumental chemicallaboratory. In closing, let me comeback to my emphasis on theimportance of the staff as opposed to the set of experimentsbeing used through a quotefrom Fromm. "There is as much intellectual intimacy in ourteaching-learning relationships asthere is emotional relationship." Teaching is a veryserious business. Learn- intimacy in a husband-wife in a ing is a serious business fromthe student's point of view.If we treat it as static, much in terms of fruitfulresults. We need to gener- matter-of-fact way, we can't expect under- ate quite a new level ofcommitment on the part ofstaff, a commitment to make our graduate laboratory courseswhat we know they shouldbe. YMCA on campus this week,I noticed on theiroutside bulle- As I walked past the extension tin board a quote fromDietrich Bonhoeffer to theeffect that a man's life is an I think that can beapplied here. The courses weteach are of what he truly believes. the experimental an extensionof what we truly believe.If we really believe that chemical education andchemistry; if we believe thatthe approach is fundamental in the price that dynamic evolution throughconstant revision oflaboratory materials is worth willing to teach hard; ifwe're willing to make itpossible for the has to be paid; if we're laboratory to students to have the time andthe freedom and thematerials they need in the without forever butting intotheir learning experience;if we teach themselves something, undergraduate laboratories, are trulyconvinced that we should aimfor quality in the of some orthodox set ofexperiments sanctioned bylong rather than toward completion accrediting under- usage andperhaps by the American ChemicalSociety requirements for believe these things, Ithink we can have remarkably graduate programs; if we really students, and better chemists better laboratories, betterlaboratory experience for our in the immediatefuture. DEMONSTRATION EXPERIMENTS FORTHE MODERN GENERALCHEMISTRY COURSE Robert C. Plumb Worcester Polytechnic Institute Worcester, Mass.

Although I didn't teachchemistry thirty years ago, I amforced by logic to the conclusion that the General ChemistryLaboratory was a more meaningfulexperience to the student then than it is now.When I am looking for ideas Ipick up a laboratory manual, demonstration assist- or a book oflecture demonstrations, or talkwith our elderly lecture ant, and find that thesuggestions are definitely notrelated to the course I am teaching in 1967; they must berelated to the course of someprevious period. The laboratories must have reinforced andillustrated the concepts of the coursefor which they were designed; otherwise why go tothe trouble?It is very difficult todesign a laboratory to provide the same quality ofreinforcement for the lecture materialtoday. In the freshman course we are nowteaching kinetics, thermodynamics,solid state structural chemistry of crystals,kinetic theory of gases--all veryadvanced concepts which are difficult to illustratein the laboratory.In my opinion some of us are nowin the period or approachingthe period where traditionalindividual student type of experimentation in the GeneralChemistry Laboratory is obsolete.The high schools are already teaching all of the fundamentallaboratory skills and techniqueswhich used to be an important part of the GeneralChemistry Laboratory. To go beyondthe technique-oriented experiments, we need morecomplicated experimental setups, tooadvanced in cost to warrant involving a largenumber of students in them. I feel that there are threeimportant facets of GeneralChemistry Laboratory work, reflecting different purposesof the laboratory experience.These are: reinforcement of lecture material, teachingexperimental technique, and involvingthe student in the really exciting part of science--discovery.The boundary condition whichI will adopt in my dis- important purpose of ourlaboratory is to reinfo:ce lecture cussion to follow is that the high schools are al- material.I feel that except for theserious chemistry student, the ready doing an adequatejob of teaching chemicaltechnic,te. Discovery, involving students in research and projectwork, is another story which Iwill try not to consider today. One answer to the problemof our need for elaborateexperimental equipment to reinforce complicated concepts isthe ersatz experiment. Let acomputer simulate an experiment and have the student,at a console, controlthe experiment. The Commission on done a good deal of workalong these lines ("The Computerin College Physics (CCP) has Physics). With This con- Physics Instruction," publishedby the Commission on College cept in instruction, thestudent could do complicatedexperiments to illustrate complicated ideas--and no chanceof breaking glassware.Perhaps the day of the ersatzexperi- ment is coming and we willbe able to argue its meritthen. For now we need experimentsthat we can do to reinforce thematerial being taught in today's lectures; we need tomake the elaborate concepts comealive for our students. the correlation of lectureand laboratory material isdifficult, It isn't enough to say that efforts in de- so we won't worrywhether or not they arecorrelated. We must make new signing more appropriateexperimental work; if we don't thestudents will not appreciate the subject matter being taught.

43 Consider, for example, teaching of solid state structural chemistry.Is it sufficient for the student to read about X-ray diffraction and crystal structures withoutbecoming involved in experimental work with them? Obviously we can't put X-ray diffraction apparatus into every freshman chemistry laboratory, but Meiners ofRensselaer Polytechnic Insti- tute has invented a Bragg diffraction apparatus, using 3 cm wavelengthmicrowaves instead of 10-8 cm wavelength X-rays, and a crystal lattice of steel ballbearings,which a student can take apart and examine, instead of a real crystal.A freshman can do a crystal structure analysis in the laboratory, using this device and the subjectof determining crystal structure by diffraction experiments comes alive for him in the process.This type of experiment, coupled with building crystal structure from styrofoam balls, such as we are doing in the laboratories at WPI, can be a real help in reinforcing the matterof the lectures. Consider thermodynamics with all of its complicated concepts: there arecertainly many experiments being done by students intoday's laboratories on measurement of thermodynamic quantities; but what about illustrating the basic thermodynamic concepts-- for example, reversible and irreversible work? Here is a handoutwhich we give our students for a demonstration experiment which we have adapted fromEberhardt's work designed to show the irreversible, reversible work concept. By raising weights inthe earth's gravi- tational field, the system does work on these surroundings(weights), and the amount of work that is done depends on the irreversibility of the manner inwhich the weights are removed from the elevator. We have added a device to measurethe heat produced by non- useful work being done on the surroundings. With thismodification one can obtain an energy balance in accordancewith the First Law of thermodynamics. The subject of statistical mechanics is certainly not an easy onefor the students to grasp; after all, a few years ago statisticalmechanics was graduate-level course material. Now students, through CBA and Chem Study, arebeing introduced to statistical thermodynamics in the high school chemistry courses! Sussmanof Tufts University has been interested in the problem of making statisticalthermodynamics come alive for the student (M. V. Sussman, American Journal of Physics, 1143-46(1966).) He states in one of his recent papers, "Demonstration devicesfor statistical thermodynamics are rare." They aren't really as rare as he implies because there havebeen several described in the Jour- nal of Chemical Education but he has developed a veryclever device for showing the Boltzmann distribution. Another device illustrating statistical thermodynamicsconcepts (R.C. Plumb, J. Chem. Ed., 41, 254-6(1964))uses a single plastic sphere, an air jet to provide variable kinetic energy and temperature, a potential energydifference between two states of the system, and a movable barrier to providevariable probability of states or variable entropy per molecule in those states.The student keeps track of the frequency with which the particle lands in either of the two statesby dropping a counter into either one of the two beakers. A student playing withthis device can soon discover that the effectiveness of entropy as a driving forceincreases with increasing temperature, that the systems seek a state of maximum entropy,and that at a low temperature systems seek a state of minimum potential energy. One of the most fundamental conceptsof general chemistry is phase equilibrium and its interpretation in terms of the statisticalmechanical and kinetic behavior of molecules. Here is a device which I have devised to makethese concepts come alive for the student.(R.C. Plumb, J. Chem. Ed., 43, 648-51 (1966)). The behavior ofmolecules is

44 simulated by motion of glass spheres on ahorizontal surface containing adepression. potential energy differencebetween a liquid and a gas.We The depression simulates the condense; as we can heat up theliquid and occasionally we see amolecule evaporate and number of molecules in the gasphase increases and the increase the temperature, the when we vapor pressure increases.We can see the irreversibleapproach to equilibrium introduce a sudden change in temperature.Actually, the behavior of thissystem quanti- tatively simulates a liquid-gasequilibrium. The results follow theClausius Clapeyron equation. teaching the kinetic theory of gases.The model simulates The device is useful in other the two dimensionalBoltzmannequation quitequantitatively. The model has many illustrating concepts of thesolid state; for example, one can seevacancy uses including anneal- and vacancy migration,dislocations and dislocation movement,grain boundaries, ing of solids, and one cansimulate the glassy state. Withcareful observation one can observe the Einstein motionof atoms in solids. the Similarly, the device isuseful in discussing theliquid state, where one sees state, rapid diffusion ofthe molecules in liquids,and short-range order of the liquid research in even the motionof clusters in atoms, a conceptwhich is at the frontiers of the theory of liquids. like to restate my position.I believe that laboratoryexperi- In conclusion I would classroom mental work should behighly correlated with conceptsbeing discussed in the It is difficult to findexperiments which illustratethe basic con- portion of this course. show, but such experi- cepts, experimentswhich show exactly whatthe teacher wants to ments can be developedand are being developed. and It's great fun for theteacher, a real pleasure tohim, to devise something new brings a gleam of understandingto the student's eye.Let's radically different which experience have more imaginativeinnovation and make thegeneral chemistry laboratory really meaningful!

45 COMPUTER SIMULATION OF LABORATORY INSTRUCTION j. J. Lagowski The University of Texas at Austin Austin, Texas The object of formal laboratory instruction on all levels may beconveniently divided into two areas; the student is expected to (a) become familiar with and appreciate certain manipulative skills, and (b) acquire a degree of maturity in themanipulation of experimental results and the strategy of designing experiments. Becauseof the increased number of students, the rising degree of sophistication of experiments,the lack of suit- able equipment, and the lack of sufficient time, it is becoming moredifficult to provide adequate instruction using classical methods. Computer-based techniques can be successfully used to individualize certain aspects of laboratory instruction. Generally,the modern high-speed computer is considered to be a device used primarily in the solutionof complex numerical problems or for processing large quantities of data in standard ways.However, it has been possible to take advantage of the rapid retrieval capabilitiesof a computer and, using special languages, to develop a system that can conduct a Socraticdialogue with a student as well as to permit him to use the computer in a normal way.In essence, the system per- mits an instructor to place his thoughts on a givensubject in the computer's memory and provides a method for the student to explore those ideas athis own pace. Once the ideas are captured, they areavailable to all students at their own convenience. Computer-based techniques can be used to simulatelaboratory experiments in several ways. Experiments can be simulated thatmake more efficient use of time. Often, experiments which are basically repetitive with respect totechnique are performed to provide the student with individualized results.Common examples of this situation are the classical qualitative analysis and experiments involvingtitrations. Computer-based methods can provide a student with practice inmanipulating experimental results after he has been exposed to the techniques in the laboratory;the student could be driven to make all the decisions he would normally make inconducting the experiment, collect his results, and come to the appropriate conclusions inless time than if he had performed the experiment in the laboratory. The saving of timecould be used to either give the student more practice or have him exposed to a greater varietyof experiments in the laboratory. Computer-based techniques can also be used to extendlaboratory instruction in certain areas.For example, it is possible to extend thequalitative analysis scheme to include many more chemical substances than appearin the classical scheme or to permit a student to develophis own scheme, if one exists, for a given combination of ions. Thus, students could be exposed toproblems that could normally be investigated only in very well equippedlaboratories. It is also possible to extend thestudent's experience in handling experimental results by simulating experiments that might(i) involve apparatus too complex for beginning students to manipulate (e.g., atomicand X-ray spectroscopy), (ii) consume a dis- proportionate amount of time if performedproperly in their entirety (e.g., a kinetics experiment), or (iii) involve equipment too expensive tosupply for a large number of students.

46 Computer-based techniques, ifproperly applied, can be used toindividualize instruction directly, as describedabove, as well as indirectly,by providing more time for the instructor who can befreed from record keeping andgrading chores.

47 AN ANALYTICAL INTRODUCTIONTO ORGANIC CHEMISTRY Rod O'Connor Kent State University Kent, Ohio

"It is a very fine thing for ourstudents to learn to think.It is, perhaps, even more profitablefor them to first learnsomething to think about." - James Cason Most organic chemists agree thatthey "learned" more realchemistry in their "organic qual." course than in anyother course in their program.The basic knowledge of nomenclature, use of the chemicalliterature, common reactionsof functional groups, and relationship between structure andproperties is inherent to thesuccessful completion of such a course and, in modern programs,spectroscopic and otherinstrumental principles are included. Typical coursesdo not, in general, depend on asophisticated background of physical chemistry or even on adetailed knowledge of reactionmechanisms or stereochemistry. Several years ago, it seemed to methat the content of an analyticalorganic course could serve as an excellentintroduction to modern organicchemistry by providing the factual background and the feelingfor the experimental foundation onwhich discussions of mechanisms, etc. could bebuilt. At the same time, the analyticalapproach to laboratory could provide a meansfor heightening student interest inand enjoyment of this introductory material. Consequently, a coursein the analysis of monofunctional organic compounds was devised as anexperimental program at Montana StateUniversity in Boze- man and wasoffered to students on an optionalbasis in the spring quarter of theirfresh- man year. The initialenrollment in 1964 was 93 and by springof 1966 the enrollment had exceeded the capacity of the360 seat auditorium so that a secondsection had to be opened. The lecture and laboratorymaterials for this course have now beenused and revised through experience ofnearly 2000 students. Of the studentsproceeding from this course into the regularorganic sequence by 1966, more than60% attained A or B grades, as compared tothe normal A, B rate of 30%. The lecture program consistedof 22 lectures, including the topics: The Nature of Organic Compoundsand Functional Groups Relation of Structure andPhysical Properties Isomerism Nomenclature Use of the Literature Analytical Reactions of MonofunctionalCompounds Spectroscopic Analysis Chromatography Introduction to Stereochemistry

A minimum of formal lecturetime was devoted to "traditional"presentation of "memory" material. Instead, programmedinstruction was provided for FunctionalGroup Recognition, Nomenclature, andAnalytical Reactions.

48 Comparative exams showed thatstudents achieved asignificantly better grasp of these topics than did studentsin a conventional organic course. The laboratory was designedfor nine 3-hour laboratoryperiods. Obviously it was drastically restrict the numberand types of unknowns used ascompared necessary to One of to a standard analyticalorganic course. Students weregiven four unknowns. these was inorganic and had tobe identified as such andeliminated before work could begin on the other three. Theremaining three were puresingle compounds selected possibilities. With one groupof students an attempt was from a published list of 175 lab- made to use a mixture of twocompounds separable byextraction, but inadequate oratory ventilation and thelack of fume hoods madethis impractical. Thegeneral laboratory approach included: Determination of the OrganicNature of the Unknown Determination of the Melting orBoiling Range and (forliquids) the Refractive Index Determination of the Solubilityand pH of the UnknownSolution Tests for Functional Groups Preparation of Derivatives Literature Search (At least oneprimary literature reference wasrequired for support of the student'sanalysis.) Interpretation of Spectra(Practice spectra were given andeach student could obtain the UV, NMR, and IRSpectra of any one of hisunknowns. Since there were far too manystudents for available instruments,mimeographed spectra were used.) Special features of thelaboratory included: Videotaped or filmed directionsfor such laboratorytechniques as melting range determination,etc. Videotaped or filmeddemonstrations of use of spectroscopicinstruments. Access to a specialundergraduate reading roomstocked with numerous reference materials,including films of sample spectra. The requirement ofstudent literature searches andmaintenance of research- type notebooks. The option of an extraunknown not in the publishedlist to be identified by chromatographic techniques inaddition to other methods. Students completing this coursewere mainly non-sciencemajors so that most either terminated their program atthe end of the course orproceeded into a one quarter course (previously described in J. Chem. Ed. ,42, 492, Sept. 1965), somein Natural Products has been times followed byshort biochemistryand/or quantitative analysis courses. As noted, those few studentswho continued with a conventionalorganic course did quite well. It would appear that ananalytical introduction to organicchemistry could usefully be incorporated into theearly part of a chemistry major program. SAFETY IN THE LABORATORY Malcolm M. Renfrew University of Idaho Moscow, Idaho To lay the foundation for our discussion of new approaches to laboratory instruction, I'll say a few words about safety in the laboratory, an essential ingredient of any good laboratory program. Why me? Anyone can tell I'm not a genuine safety expert:I'm not wearing safety glasses, nor safety shoes, nor a hard hat. You may wonder what are my qualifications for speaking on safety in the laboratory.First, I do have a sense of mission which stems from gratefulness that I escaped serious injury from bad practices in my own student days. I'm pleased indeed that I wound up with as many fingers, hands, and eyes as I started with, more as a result of luck than sound practice. Also, I do have a feeling of urgency to encourage an active reduction in laboratory hazards for the current generation of students. This has led to my service on the ACS Safety Committee and committees of the Campus Safety Association. Also, I have historical appreciation of safety programs, since I have personally witnessed the rise of industrial safety programs and now am watching the growth of safety consciousness in academic institutions. a) During summer work in a sawmill 40 years ago, I saw, several times each year, men lose fingers and hands; I witnessed a filer lose an eye to asplinter of flying steel; and a friend seriously injured by a practical joker with a high pressure air hose. b) There have been marked improvements in safety practices in that same sawmill in later years. Guards are now installed on saws and moving machinery; there is eye protection in the shop, enforced rules against horse play, and active safety interest both on the part of management and union. c) Sharp reductions have been made in all types of industrial accidents over these same years. Accident rates have declined as shown by thefollowing figures for lost-time injuries:in 1926, 32 million man hours; in 1966, 7 million man hours; and we have much more complete reporting now, which makes the latterfigure a more certain measure of progress. d) As a chemist I take pride in the fact that good chemical companies have a rate of only 3 lost-time accidents per million man hours worked. The chemist fathers of our students are now safer at their jobs than in their homes. A!so, men who work for companies with good safety programs are safer in their homes than are the general public. There is a real carry-over of safety consciousness from the job to home, despite the lack of safety supervision after working hours.

e)It was my good fortune that my first professional job was with a safety first company - duPont.

50 this 1) duPont enforced an eyeprotection rule whenother companies said couldn't be done (I was ablehappily to carry this practiceinto laboratories of two othercompanies). 2) Smoking was restricted toapproved areas. 3) Protective guards weremaintained on all machinery. 4) Safety cans were suppliedfor flammable solventsand there was protection against static sparkswhen filling cans withsolvent. 5) Routine checking ongood exhausts waspracticed. 6) No one was permitted towork in the laboratoryalone. in industry, peoplewho didn't take safetyserious- f) As safety consciousness grew lost his job because ofdistilling ly suffered for badpractices .(I recall one chemist who too large a quantityof flammable liquid in aglass flask.) accident in But accidents still seemto happen despite ourbest efforts. When an people close to me, Ibecame impressed with thefact that the duPont duPont affected some paternalistically. Accidents costthe safety program wasmotivated economically - not company money bothfor facilities and forpersonnel. has a cor- The rise of safetyconsciousness in academicinstitutions now probably In many states it is nowpossible to sue academicinsti- responding economicmotivation. Also, as school tutions for failure to take propercare of youngpeople entrusted to them. prosperous, theyhave become more likelytargets for suit. teachers have become more in claims jargon, i.e. , suethose who (This is known as theprinciple of the deep pocket can pEoff when judgments arerendered againstthem!) dislocations No large number ofaccidents happen inschools each year, but major accidents and of fireswhich have crippledchemistry can occur. Weall know of disabling have a long way to programs in our own orother institutions overthe years. Colleges do of a good industrialfirm, but they have a real go in achievingthe low accident record the journal of Chemi- stake in improving theirrecord. An article bySchmitz and Davies in 1967 on liability cases,emphasized the fact that: youmust not cal Education for August, accident takes place only teach and maintainsafe practices in thelaboratory, but after an you must beable to prove that youdid teach safe practices. legal liability but also tobuild safety consciousnessoverall, we Not just to reduce the one attached do ask students at theUniversity of Idaho to sign astatement similar to to the instructorand keeping one copy inthe notebook. And we to this paper, giving one almost worse to havethe do urge our instructorsto enforce thesepractices, since it is knowledge of good practice,but neglect it, than tolive in blissful ignorance. he wasn't con- Actually, any instructorwho tries to argue,after an accident, that impact-resistant glasses inthe laboratory willhave scious of the need forthe wearing of requiring that in court theseday'S when half of our stateshave enacted laws a tough time shops. eye protectionbe routinely worn inschool laboratories and the safety glass But I don't want toimply that there is acompletely simple answer to and I sat in on the ACSSafety Committee'ssession in Chicago problem. Dr. Carl Stevens glasses in school labora- to draw up arecommendation for Societyendorsement of safety it is difficult to definejust what kind of eyeprotection should be tories. Unfortunately goggles, and these have adopted.In many statesthe new laws are interpreted to mean

51 now been adopted at Washington StateUniversity as the standard for all laboratories; but many teachers in California object to these becausethey fog over in humid laboratories. At Idaho, plastic visors which pass the specifications of the American Standards Associa- tion for strength and also protect against direct splashes are considered safe for general use; goggles are required only in morehazardous situations. It is my personal conclusion that eye protection, protection against solvent fires, and safeguards against electrical shocks are the critical points in school laboratories. Students are more apt to know that H2S , mercury vapor, and certain chlorinated or aromatic solvents are toxic than to know about explosive mixtures of air and solvent or that 110 volt (or 50 volt) electrical circuits can be lethal.(Fibrillation of the heart, which may be induced by low voltage currents, is just as deadly as a massive shock and may be even less susceptible to first aid treatments.) They also don't know that they are potential victims of an accident across the bench, which means that wearing eye protection is essential at all times, not just when they personally are performing hazardous experiments. Also, it is my impression that many students and teachers are not yet aware that un- consciousness may come from a breath or two of an oxygen-free atmosphere with quick death following in a couple of minutes; or of the explosive hazards met when a conventional household refrigerator is pressed into service for chemical storage. In particular I believe that we should urge the formation of a broadly based safety committee in every department. We also should urge outside inspection of college facilities at regular intervals by experts in fire protection.In addition, we should coun- sel against the use of perchloric acid or perchlorates in undergraduate laboratories. (Urge caution in graduate laboratories, toc, if perchloric acid is in use!) We should eliminate experiments from introductory courses which have recognizable hazardsof appreciable dimensions. The reagents in our undergraduate laboratories should belimited to those in immediate use. What safety references can be recommended to a collegefaculty? a)A number of inexpensive references are available: 1) Upjohn's "Safety in the Laboratory" (free). 2) duPont's "Condensed Laboratory Handbook" (single copies free, low cost in large quantities).) 3) "Laboratory Design Considerations for Safety" of the Campus Safety Association ($1.50) has good guidelines on safety in facilities, i.e. hoods, solvent handling, etc.I personally recommend membership in CSA, which too few faculty members join(it is now largely made up of college safety men, but facultymembership is increasing). The CSA puts out a useful monthly safety letter which costs only $200 per year and can be obtained through the Campus Publishers, 711 N. University, Ann Arbor, Mich. 4) Alpha Chi Sigma: Safety Practices in the Freshman Laboratory. 5) "Safety in the School Laboratory" Bulletin #15 of Science Bulletins Education Center, Columbus, Ohio 43216 (free). 6) Safety manuals put out by chemistry departments in colleges, e.g., University of Illinois at Chicago, undergraduate division(20). 7) Safety Manual of a university, e.g., University of Kentucky's "Safety Program and Standards for Safety" (general reference for all campus use; many institutions have developed suchmanuals and will provide them on request).

52 reprint ofcolumns editedby 8) "Safety in theChemistry Laboratory", Norman Steere inJ. Chem.Ed. , $3.00. and AccidentPrevention inChemical 9) Fawcett andWood, "Safety Operations", JohnWiley (1965). "Handbook of Safety"Chemical RubberPublishing 10) Norman Steere, Company, (1967). accident hasoccurred? What to do after an don't practicemedicine without alicense! 1) What not to dofirst: student healthcenter, but Send minor cuts,burns, etc., to your there is a the studentand providetransportation if do accompany be more thanminor. prospect thatthe accident may from practices forretarding theflow of blood 2) Learn first aid respiration. Afaculty membermust arterial cuts andfor artificial (Arterial blood aid of this kindwhen it isneeded. be ready to give artificial respiration flow must bestopped within oneminute and within a coupleof minutes!) is essential if disastershould strike. 3) Call for medicalhelp promptly UNIVERSITY OF IDAHO CHEMISTRY DEPARTMENT General Laboratory Instructions

1. Avoid waste of gas, water (both tap and distilled), filter paper, and materials of any kind. 2. Use only your own reagents and return reagent bottles promptly to their proper places.(Do not return excess reagents to supply bottles.) 3. Dispose of solids by placing them in waste jars, unless they are readily water soluble. 4. Use the lead trough in the center of the desk for the disposal of water only. Dis- pose of small quantities of nonaqueous liquids by pouring them into the sinks.If such liquids are corrosive or flammable, flush them down with plenty of water. Larger quantities of flammable solvents should be placed in the metal containers provided for this purpose. Substantial quantities (more than 10 ml.) of such solvents must not be poured into the drains since they constitute an explosion hazard. If acids or alkalis are spilled on the desk or floor, wash the surface at once with plenty of water; then wash the desk with sufficient boric acid solution in the case of spilled alkalis and sodium bicarbonate solution in the case of spilled acids so as to neutralize the acids or alkalis that have penetrated intothe wood; then wash the desk once more with plenty of water. 5. When leaving the laboratory make certain that your gas and water are turned off and that your desk is clean and neat. 6. Maintain an orderly arrangement of the apparatus and materials in your desk. The desk drawers and cupboards are inspected periodically and rated on the basis of neatness and cleanliness. 7. Use only the balance assigned to you. Special Safety Rules

1. Wear approved eye protection in the laboratory continuously. This means eye covering which will protect both against impact and splashes.(If you should get a chemical in your eye, wash with flowing water from sink or fountain for 15-20 minutes;) 2. Perform no unauthorized experiments.

3. In case of fire or accident, call the instructor at once.(Note location of fire ex- tin uisher and safety shower now so that ou can use it if needed. Wet towels are very efficient for smothering smallfires.) 4. You must go to the Infirmary for treatment of cuts, burns, or inhalationof fumes. (Your instructor will arrange for transportation if needed.) 5. Do not taste anything in the laboratory.(This applies to food as well as chemicals. Do not use the laboratory as an eating place, and do not eat ordrink from laboratory glassware.)

54 avoid breathing fumesof any 6. Exercise great care in notingthe odor of fumes and kind. chemical reagents.(Use a 7. Do not use mouth suctionin filling pipettes with suction bulb) (Protect your hands with atowel 8. Don't force rubber stoppersonto glass tubing. when inserting tubing intostoppers.) essential 9. Confine long hair when inthe laboratory.(Also, a laboratory apron is when you are wearing easilycombustible clothing. Such an apronaffords desirable protection on alloccasions.) 10. Never work in the laboratoryalone.

I have read thelaboratory rules and willobserve them in my chemistry course.

Signature

Date

(Return one signed copy toinstructor).

55 WHAT SHALL WE TEACH NON-SCIENCE MAJORS? Edward C. Fuller Beloit College Beloit, Wisconsin informed citizen should be conversant with the larger principles of science, the dynamic potential of scientific research, the main contemporary currents of scientific effort and their relationship to social forces. With such an understanding, an intelligent citizen can make intelligent judgments between good and bad policy on scientific and technical matters. Without it, he can hardly participate fully in a scientific democracy." These words of Glenn T. Seaborg, Chairman of the U.S. Atomic Energy Commission, cannot be improved upon as a succinct statement of what science for the non-scientist is all about. The teacher who undertakes the formidable but exciting and rewarding task of teaching science to the student whose chief interest lies in some other field will quite properly have his own personal interpretation of what research can do for man and how it is likely to affect our lives. A consultant can be of little use to him here. But "the larger principles" serve as a common denominator of understanding when contem- plating the rapidly shifting interplay of dynamic research and technology in our society. It is with these principles that we shall be concerned in this brief paper. When we plan a course we must ask and answer three basic questions: (1) What background in science will most of our students have? (2) What do we want them to accomplish in the one or two semesters we shall have together? (3) What principles will serve most effectively as the vehicle for these accomplishments? As a brief summary of "the larger principles" I would suggest the following: 1. All substances are composed ultimately of tiny particles (atoms, molecules, or ions) in rapid motion. 2. The heat content of a substance is proportional to the energy of motion of these ultimate particles; heat changes solids to liquids and liquids to gases by increasing the energy of motion of the ultimate particles. 3. All matter is made up of different combinations of the atoms of some hundred or so elements. 4. Atoms of all elements are composed of protons and neutrons packed in a tiny nucleus surrounded by a cloud of electrons; atoms are mostly empty space. 5. The atoms of different elements differ in the number of protons and neutrons contained in the atomic nucleus and in the number and arrangement of electrons in the cloud. 6. Atoms of elements with similar chemical and physical properties have similar distributions of electrons in the cloud. 7. The masses of atoms are known so that the relative masses of the substances taking part in a given chemical reaction are known.

56 8. Energy is always either produced or consumedwhen a chemical reaction takes place; the amount of energy involved is always the samefor the same masses of substances reacting in a given way. 9. Energy is the capacity for doing work; work is measuredin terms of a force acting through a distance. 10. In all but "atomic energy" reactions the total massof materials entering into a reaction exactly equals the total mass of theproducts formed, within experimental error. 11. In all but "atomic energy" reactions there is no lossof energy when one form of it is transformed into another. 12. Matter is an extremely concentrated form of energy, andconversions of one into the other can be made by "atomicenergy" reactions; in these conversions, the total of mass-and-energy before the reactionis equal to the total of mass-and-energy after the reaction. 13. All living things are composed of one or more cellswhich contain a substance called protoplasm. 14. Foods ingested by living organisms are utilized throughchemical and physical processes in the organism both to build tissues and toproduce the energy necessary to maintain life. 15. Several different classes of food, servingdifferent purposes, are required for the adequate nutrition of man. 16. Living things can arise only from other livingthings of the same kind; all life tends to reproduce its own kind. 17. The creatures of today have descended bygradual changes from different and usually simpler creatures of the past. 18. The rocks in the crust of the earth contain arecord of how the earth and life on it have changed in the past. 19. Past changes in the earth's surface and theliving forms inhabiting it are adequately explainedby processes now in operation. 20. The conception of the world onebuilds from his sensory perceptions does not correlate completely with thephysical world which produces the stimuli perceived by his senses. When one looks at this list, it is obviousthat he must first decide whether he wishes to teach a course cooperatively with acolleague in another department or limit himself to those principles which are mosttypically chemical. From about a thousand replies to questionnaires sent to a total of sixteenhundred institutions of higher education,it appears that about 40% of the coursesin science for nonscience students inthis country are multidisciplinary, that is,include material from two or more departmental disciplines - astronomy, biology, chemistry,geology, mathematics, and physics. Courses in "physical science" are taughtin about two-thirds of the two-year colleges. In four-year colleges this combinationof disciplines in courses for nonsciencestudents outnumbers all others, but courses includingbiology are quite frequently encountered. Of the courses involving only two disciplines,chemistry-physics far outnumbers all other combinations. To lab or not to lab - that is the questionthat plagues every science teacher. In this writer's opinion,a science coursewithout a lab is like a ship without a rudder - better than no ship, but not much! The laboratory-rudderis needed to give direction and control to the course of the ship - or the ship of the course,whichever you prefer. How- ever, in all fairness it must be pointed outthat about 40% of the multidisciplinary

57 courses in science reported in answer to the questionnaire are being taught without bene- fit of laboratory - and another 4% with only one hour of lab per week. A few such courses entail four or more laboratory hours per week. Most of the other 55% have two or three hours of lab per week. A third of the multidisciplinary courses run for one semester and another third for two. The remaining ones involve various other lengths of time. The new teaching aids such as films, film loops, video tapes, and remote stations for asking questions of a computer and getting answers promptly will undoubtedly be of great help in relieving both the student and the teacher of much of the drudgery which has bedeviled laboratory work in many introductory courses. The stimulus toward the use of such aids has been provided by the AC3 Committee on Teaching Aids under the chairmanship of W. T. Lippincott. We need to do more experiments in which students gather data and use them immediately to draw some important conclusions about some basic principle in science. The Committee on Teaching of the Division of Chemical Edu- cation in the American Chemical Society is stirring up new brews of laboratory experience under the leadership of H. A. Neidig at Lebanon Valley College. The many inexpensive paperbacks dealing with special topics in chemistry and other sciences can be used liberally for spicing up the student's interest in broad and sometimes abstract principles. The "Case Histories" being published by the AC3 Committee on Science for the Non- Science Major under the chairmanship of Robbin C. Anderson will be useful to any teacher planning a course of this type. Anyone who is ready to roll up his sleeves and plunge into the heady activity of mixing up new combinations of scientific experience for the non-scientist to indulge in will find plenty of help from his colleagues engaged in the same enterprise.

58 -

CHEMISTRY FOR NON-SCIENCE COLLEGESTUDENTS James F. Corwin Antioch College Yellow Springs, Ohio It seems that I have beentalking about this problem since I began to teach incol- lege in 1941. When I arrived atAntioch, I found myself in a situation where there was concern about thewholly educated person.It was a new idea to me then, that somein- tellectually oriented non-scientistsreally wanted to know about science and thatthey even considered itrespectable to know about it.In the college it was required that one- third of the general educationof the student,which consisted of aboutone-half of his effort in obtaining a degree, wasdevoted to the study of science. On becoming aware, I was soon converted to theidea that this problem was just as important asthat of turning out well trained chemists. Now, after twenty-five years,I find myself still talking about theproblem.I wish that I could say that now I canoffer a solution. Instead I will describe someof our efforts and indicate where wethink the problem now stands. The first indication of real concern on ageneral level came in the late 1940's when the atomic bomb brought home tothe_non-scientist that the existence of the worlddepended on understanding howsuch a weapon could be developedand how it would affect the political nature of the world. Combined courses called PhysicalScience, Life Science, and Earth Science were tried and met with varying degreesof success.In a survey of these programs made in 1955 it was concluded that the successof these depends on the devotion andcommitment of the teacher to the idea. Wherethey were tried and-assigned topeople not having the commitment (usually to the youngermembers of the department) they werefailures. The Sputnik was the next disturbinginfluence. A great deal of money and time has been spent in the last ten years on improvingsecondary science education and in general it has been successful. The studentscoming to college are better preparedfor science than ever before.It is interesting to note,however, that the improvement in preparation has not produced an increased interestin science as a career. Even thoughenrollments have gone up the number of peopleinterested in science as a career hasremained constant or even dropped a little. Many have attempted to analyze thissituation, and all sorts of reasons havebeen given. Too much work, the poor imageof the scientist, the lack of disciplinein present education, poor pay of scientists and manyothers.I believe that while the young person now has been so saturatedwith the idea that science cando anything, the romance that is coupled with working in the frontierof things has gone from scienceand is now centered in working with people and delvinginto the mysticism of the fine arts.Even those few really interested in science now are attractedto biology and biochemistry, ratherthan the physical sciences. The fact that fewer of the totalpopulation are now concerned withthe scientific profession, makes it more imperative that wereach those having these other concerns with a basic understanding of science. I have come to the conclusion that there aretwo major facets to the problem. One of these is mechanical and the other is content.The former involves the question of "how do people learn?" and the second, "whatshould the non-scientist learn?" At the AC3 Conference on Chemistry forNon-Science Majors held in Dallas, Texas, April 15 and 16, 1966, I reported on the organizationof a new experimental program at Antioch College. The case history presentedthere has since been published inthe AC3 Newsletter VII, January, 1967, and is availablein more detail on request to AC3. This program has been in operation for fourstudent quarters, and the second groupof students are just completing the program.I will review here the mainpoints of the program and then proceed to give you what we think wehave learned from it. The original program offered in 1965-66developed by taking the science area approach. All individual science courses werediscarded and a series of thirty presentations from all of the departments wereoffered. Eleven independent studies programs and six special seminars completed thestudies.Skills programs in basic mathematics, physics and chemistry laboratory,and graphics werealso available to the student. Short seminars and discussion group meetingsaccompanied each of the thirty presentations. The student and his preceptor worked out a programwhich was designed to fit the goals of the student and the backgroundalready exhibited through a physical science placement exam taken during the firstweek on campus. The whole first year program could be waived by a sufficiently high score on anachievement examination. As a consequence, most of thestudents who came with a commitment to sciencestudy waived the special program. The second year of the totalcollege program has remained unchanged. The general goals for the program were: 1.To encourage the student to assume moreresponsibility for his program and for his education. 2.To give the student a chance toexplore his own ability to learn by independent study. 3.To provide leeway for adjustment tothe demands of a college program. 4.To prepare him for entrance into secondlevel courses in general education and in his field. 5.To help him select his major fieldby allowing him to sample several departmental offerings in the first year rather thantying him down to one, or at a maximum two. In order to do adequate evaluationof such a program, an office of educational research was set up two years before the program wasinitiated. A group of studentsfrom all areas were selected during that time to act as acontrol group for the new program. As similar a group as waspossible to select was assembled from thestudents participat- ing in the new program. The firstpreliminary report on the success in attainmentof these goals was issued by the testing office inNovember. These are the indications:

1.A larger number of the experimental groupfelt that they were now ready to assume more responsibility fortheir education. Almost one-third,how-

60 ever, felt that the college really should have done this for them. 2.As was expected, a much larger number of the experimental group found that independent study was an adequate way to obtain an education but that it was more work. 3.A sizeable decrease in drop-outs was experienced but this is tempered by two things: the draft situation among the men and the fact that each student was assured of being in good standing at the end of the experimental year. However, if he did not perform adequately in any area, he had to complete the work as an elective before he could graduate from college or before he could enter the second level courses. Table I shows how my preceptoral group of thirteen students completed the first level work. This group was typical of the fourteen other groups.

TABLE I PRECEPTORAL GROUP Preceptoral Team -- Instructor, upperclass male, upperclass female. S.S.=Social Sciences -- Non graded courses received S or U. P.S.-Physical Sciences. H=Humanities -- Graded courses received, A, B,C,D, I or F. F.Y.P.=First Year Program. Grade point average (G.P.A.) usual 4 points = 1 hr. of A credit. I was assigned thirteen students:7 men, 6 women from two halls which were entirely first year halls except for 4 upperclass preceptoral fellows. The table below lists them in order of their academic promise as derived from C.E.E.B. scores. Thirty credits toward graduation were given for first year program work.

V M Work completed Work com- Number Sex CEEB CEEB First year pleted 2nd level 1. M 725 683 P.S. Area. FYP com- Carried 16 hrs. pleted 1/2 Humanities 5 U5 I 0SS 5 D+ G.P.A.1.0

2. M 703 518 FYP completed all Carried 15 hrs. areas 30 credits 5 A 10S G.P.A. 4.0

3. F 690 774 Completed FYP Carried 16 hrs. 36 credits +10 by 6 S 10B exam G. P .A. 3 . 0

4. 683 788 Completed FYP Carried 18 hrs. 36 credits + 10 by 18 A G.P.A. 4.0 exam

5. F 657 492 Completed FYP Carried 15 hrs. 36 credits + 5 Adv. 10A 5 D+ Placement G.P.A. 3.0

61 6. F 648 617 Completed FYP Carried 16 hrs. 36 credits 10B 5C 1 S G.P.A.2.66

7. 632 735 Completed P.S. Carried 11 hrs. 1/2 Humanities 5 I 6 S 1/2 SS 30 credits G.P.A. 0 + 10 by exam

8. 617 592 Completed Hum Carried 11 hrs. 1/2 SS 1/2 P.S. 5 A 6 S 30 credits + 5 by G .P .A. 4 . 0 exam

9. 625 606 Completed FYP in Carried 10-1/2hrs. Mexico Hum. 1/2SS 8 A 2.5 B No P.S. G.P.A. 3.7 30 credits

10. 612 592 Completed Hum Carried 13 hrs. area 1 0 C 2.0 3 5 1/2 P.S. 1/2 SS G.P.A. 2 . 0 30 credits

11. 592 534 Completed Hum. Carried 16 hrs. 1/2 P.S. 1/2 SS 10 C6 U 30 credits G.P.A. 2.0

12. 546 615 Completed FYP Carried 16 hrs. 30 credits B 10 C 5 S I G.P.A. 2.66 .,. 13. '294 324 Completed Hum. Carried 11 hrs. in FYP No P.S. 5 B (lit.) No SS 6 S 30 credits G .P .A. 3.0 7 Physics Physics 8 Undecided Undecided 9 Social Work Languages 10 Undecided Languages 11 Undecided Undecided 12 Geology Anthropology 13 Social Work Social Work In spite of the rather successfulresults of the overall college program, the program in the physical science area was much less satisfactory.It was not that the students did not complete their science requirement inthe first year, but their selection of work from the general program was quite a shock to thephysics and chemistry departments. Nearly all of the students selected Biology, Earth Science, and Engineeringsubjects as a means of fulfilling their general education requirements and only a few lessthan 10% chose to become involved in chemistry, physics, and mathematics. None changedfrom other areas to science. In view of this development and a survey of student andfaculty opinion,a modified program was offered to the1966-67 group of students. Instead of chemistry and physics being spread over the whole first year, sequential seminar type offerings weregiven which were contained in one period of school. Major presentations weredistributed throughout the period. This modified plan is presented in Table III.

TABLE III

PHYSICAL SCIENCE PRESENTATIONS OFFERED IN A SEQUENTIAL PATTERN DURING ONE PERIOD: SUMMER 1966

Subject Department Responsible for Offering 1.Study of the Earth I: Basic Concepts in Historical Development: Time & History Geology 2.Structure of Matter: Qualitative and Historical Development of the Kinetic Molecular Theory Chemistry 3.Galileo - Historical Development Physics 4.Ways of Knowing in Science and Engineering Engineering & Philosophy 5.Energy: A Semiquantitative Approach Physics 6.Physiological Chemistry: A Discussion of the Present Status Chemistry 7.Newton: A Historical Approach Physics 8.Study of the Earth II; Composition & Process Geology 9.Physics "Circus" - A Demonstration Physics

63 Table III, continued Sequential Seminars

Title Meetings per Week Description Physics A 5 For B.S. Student Choice Calculus A 5 For B.S. Student Choice Mathematics I, II, III, N, V 3 M I Sets M I Geometry M III Functions M IV Relations M V Nature of Modern Algebra Copernican Revolution 3 For General Education (Discovery Approach)

Structure of Matter 1 For General Education

Introduction to Chemistry 1 For General Education and preparation for advanced chemistry Laboratories in Physics and Chemistry The results of this change have not yet been evaluated but more than four timesas many students were involved in the physics and chemistry portions of the program. The change clearly indicates a tendency to go to a more courselike program. A second group of students are now involved with a somewhat different program which attempts to emphasize the more successful portions of both of the first two trials. Table IV is an outline of the latest program.

TABLE IV

PHYSICAL SCIENCE PRESENTATIONS OFFERED IN A SEQUENTIAL PATTERN DURING ONE PERIOD: FALL 1966

Subject Department Responsible for Offering 1.The Earth Model: Problems and Implications Geology 2.Atomic Structure: Historical and Semi- Quantitative Approach Chemistry 3.Liquids: Condensed Gases or Molten Solids? Chemistry 4.The Properties of Water Chemistry 5.What Makes Blood Red? Chemistry 6.Firecrackers, Rockets, and Nuclear Reactions Chemistry

64 Table IV, continued Sequential Seminars Title Meetings per Week Description

Physics A 5 For B.S. Student Choice

Calculus A 5 For B.S. Student Choice

Mathematics 3 Several S ections 1.Set Theory: Language in Crisis 4 weeks 2. The Axiomatic Method: Generalizing Truth 3 weeks 3. Topics in Foundations of Mathematics 3 weeks Descriptive Chemistry 2 A combination of Qualita- tive and quantitative approach. Group divided into General Education and Preparatory Interests

Physical Science 1 Divided into sections Task force approach 1.From Atomos to Atom: Historical 18thand 19th Century 4 weeks section 2.Birth of a New Physics: Galilean- Keplerian-Newton:an Achievement 4 weeks section 3.Energy: The Physicists Concept The Current Social Problem 4 weeks section

A SERIES OF SHORT SEMINARS BASED ON THE FIRST PRESENTATION "THE EARTH MODEL." Title Meetings per Week Description 1. The Origin of Planet Earth 2 Earth Models - 2 weeks 2. Formation of the Elements 1 Theories - 3 weeks 3. Visitors from Outer Space 2 Meteorites - 3 weeks 4. Crystals: An Introduction 2 Crystal Structure - 3 weeks 5. Composition of the Earth 2 Processes - 3 weeks 6. The Earth Model 2 Continuation of Presenta- tion - 2 weeks 7. The Origin of Continents 2 Continuation of Earth Model - 2 weeks Physics and Chemistry Laboratories are used. This modified program has not been evaluated yet but, again, an increase in the number of students involved in the physics and chemistry portions was noted. The number in Earth Sciences has remained the same. Offerings in biology are being de- ferred to the second period. These are very similar to those in the original program. The preliminary conclusions drawn from experience this far are:

1.A sequential approach to chemistry is more successful and preferred by both teacher and student. 2.Independent study plus seminar and discussion periods is quite usable in chemistry. 3.There has been no demand to return to the lecture-quiz section method by either students or teachers. 4.A full evaluation must wait until next summer or fall. I would like to add a word of caution to those experimenting with new ways of doing things in chemical education or for that matter any type of education. To reorganize and redo a program takes a tremendous amount of time. The original program was set up by obtaining money from the Esso Corporation that paid for time freed from other work to develop new approaches. In order to continue the experimentation, Antioch College has received a grant of $400,000 from the Sloan Foundation which will allow nine teacher quarters per year to be freed for program development each year for the next five years. The problem of laboratory work in this experimental program has been approached by new methods also. The laboratory work has been made available on a continuous basis by using the carrel-type of permanent set-up which is open to student use during the afternoon, six days per week, and three evenings. This set-up is quite similar to that proposed by Postlethwaite at Purdue University and used in teaching botany. The laboratory table tops have been divided into carrels in which all of the equipment necessary for the experiment is available. An instruction notebook goes with each carrel. Where techniques are new, a short film, both loop and projector type, is available. An assistant or an instructor is present at all times. Each student keeps a notebook and completes a question list which he submits to the instructor for evaluation.

66 OPENING THE DOORS TO CHEMISTRY FOR ALL STUDENTS:

INTRODUCTORY CHEMISTRY FOR TWO-YEAR COLLEGES William T. Mooney, Jr. El Camino College Via Torrance, California Because the type of institution tends to determine the characteristics of its chemistry program we should consider first what is meant by a two-year college. These institutions are the public community colleges, public junior colleges, private junior colleges, two- year technical institutes and two-year centers of university systems. The public institutions are often characterized as open-door, comprehensive, community colleges. The concept of opening the doors to chemistry for all the students is a consequence of the open- door, comprehensive, community college philosophy. The "open door" means entry into the college is generally unrestricted.It means that many courses and many curricula must be available. Some courses will be within the range of a student's interest and within the purview of his abilities. Some will be outside his interests and some beyond his ability. The student need not choose what lies outside his interest. He should not be allowed to choose that which clearly lies beyond his ability. Unfortunately, many two-year college administrators and faculty do not realize that the open-door college philosophy does not require every curriculum and course to be open-door. It does require a variety of curricula to match the potentials of a variety of students. "Comprehensive" means a commitment to a multiplicity of educational functions or purposes. Six functions are generally listed:1) education for transfer, or the lower-division parallel function; 2) education for occupational competence, or the career training function; 3) education for living, or the general education function; 4) counselling and guidance; 5) community service, and 6) education for overcoming deficiencies, or the remedial or salvage function. The "community" concept arises because the colleges may be wholly or partially gov- erned by local authorities, they may receive considerable financial support from local sources, they may be tuition-free, or relatively low-cost, compared to other higher educational institutions.Furthermore, they generally respond quickly to the educational needs of their communities,and by the extended day scheduling of classes, they educate and train all segments of the community, from 16 years to 80. The development of chemistry programs for two-year colleges must be viewed in terms of the open-door, comprehensive, community philosophy and the six functions mentioned earlier. To fulfill the education for transfer function, a college must provide a well-rounded or complete lower-division college program for persons who desire to continue their education in an academic or professional discipline such as chemistry, physics, biology, engineering, or dentistry. Many students cannot qualify for the university or the state college upon high school graduation, but are potentially capable of obtaining a baccalaureate degree and often a doctorate.In California the university system accepts only the top 12-1/2 percent of the high school graduates and the state college system, the top 35 percent. In Florida, which has only a university system, these institutions accept only the top 40 percent. The two-year college must provide an opportunity for the unqualified or ineligible students to demonstrate their capacity to maintain, over an extended period, an acceptable standard of scholarship in subjects of collegiate level, so that they can enter the four-year

67 institutions as fully qualified juniors. Reports from the universities indicatemany "ineligibles" transfer, graduate, and continue to graduate degrees. El Camino College, in its twenty years, can identify many such students who have received Ph.D.degrees, some in chemistry, and others who have earned professional degrees in fields such as medicine and dentistry. Two-year colleges also enrollmany students eligible to enter the four-year college direct from high school but who, for variousreasons, elect to attend the two-year college and then transfer. If a two-year college is to maintain college level standards in college levelcourses it must be concerned about and maintain the integrity of its transfercourses and program. Therefore, for students not qualified to embark upon a college level courseor program, the college must provide remedial programs. They may be high school equivalentcourses for students who possess insufficient skill or competence to master college level work.

There are three implications of these considerations for the chemistryprograms of two- year colleges.First, the college must offer a general chemistrycourse equivalent to that of the corresponding university and state colleges. Second, it must offera second-year chemistry program equivalent to that of these institutions.(I purposely used the term equivalent rather than identical or parallel.) The third implication is thatthe college must provide a means of developing a student's level of performance and understandingso he can enter the general chemistry course with a reasonable chance ofsuccess. To fulfill the function of education for occupational competence the college mustpre- pare its students to enter gainful employment upon completion of a two-year course of study and with a reasonable chance of succeeding and advancing. There iscurrently much interest in and concern about chemical technicians, who are generally classifiedas being semi-professionals. They represent one part of a continuous spectrum of scientific and technical jobs for which the two-year college must train and educate students. This spectrum has four broad bands. The first band includes craftsmenor skilled tradesmen; second, highly skilled or industrial technicians; third, semi-professionals or engineering and scientific research technicians; and fourth, professional engineers and scientists. The band boundaries are diffuse rather than discrete. The bandsare characterized, as one moves from the craftsman to the professional, by increased complexityand intellectual content of the job demands. Two-year colleges must developprograms which will train each group of students what they are required to do on the job and educate them in what they are required to know to perform effectively in their jobs. The provision for the professional is a part of the transfer function. The implications for chemistry programs is that the college must provide instructional programs, curricula and courses for the craftsman, the highly skilled, and the semi-professional if it is to fulfill its occupational education function. There must beas great concern about the integrity of these programs as that of the transfer program. The general education function requires that we provide general liberalizing education for transfer and occupational students.It also requires that we provide educationalex- periences of a generalized nature for those members of our community who have neithera higher educational degree goal nor an occupational educational goal. A fifth implication for chemistry programs is that the college must provide part of the general education program in science for the non-science and non-technical students.

68 The counselling and guidance function isimportant because we are obliged toprovide a multiplicity of programs for aheterogeneous student body. We have to dealwith students who come to us and say "I want to be achemist, or a doctor." Thal may or may not be a realistic goal. The sixth implication for the chemistry programsof the two-year colleges is that they must develop a philosophy and programfor the placement of students in chemistry courses at the place where the student has the mostreasonable chance of succeeding and where he will obtain the education and training in chemistry bestsuited for his educational goal. The two-year college situation is such that studentsshould not be allowed to enter a college level program when they obviously are not readyand will probably "sink". There is considerable evidence that through counselling, guidanceand remedial programs large numbers of students can be salvaged and thereby succeed inswimming the whole distance. The community service function requires thatthe two-year college identify all of the educational needs within the local community, be theyhighly specialized or general, and respond to these needs by providing suitableeducational programs. A seventh implication for the chemistry programsis the need to develop a series of specialized courses or programs related to chemistrysuch as a nuclear science course, or a water chemistry program, or ascience lecture series. The salvage function and the implications related toproviding a remedial program in chemistry have been previously mentioned. Introductorychemistry programs of the two- year colleges have tended to evolve ordevelop in four general phases. The first phase starts when a college is new.Older colleges with limited enrollments may remain in this phase for many years.Phase one introductory chemistry consists of a single one-year course, often entitled General Chemistry,and characterized by the complete lack of, or near lack of, mathematical and scientificprerequisites. All students who are required to or who elect totake chemistry are enrolled in this course: chemists, chemical engineers,physicists, biologists, engineers, pre-medicals, pre-dentals, nurses, all forms of technicians, and non-sciencemajors. The problems and pressures characteristic of phase onebegin to appear immediately. If the course is so taught that students are adequately prepared foradvanced work in chemistry and related fields, what happens to the various technicians andnon-science majors? The mathematical and scientific backgrounds, abilities, and interestsof these several groups of students are extremely diverse. Thediversity within each major group is considerable for there may be in the group high school valedictorians, andother high school graduates and adults who have never attended high school but can profitfrom instruction. The frustrations of drop- outs and failure often become so great thatthe college administrators become concerned. If the faculty reduces the scientific contact andmathematical orientation their transfer students do poorly at the transfer schools. When the pressures from this melting-pot situationbecome so great and/or the number of students increases significantly the collegetends to enter phase two of the development of its chemistry program. Some newcolleges start in phase two if they feel initial enrollments will justify such a program.

69 The second phase is characterized by the introduction ofa second introductory chemistry course. Students are divided between these twocourses on the basis of their majors or educational goals. One course we will call "general chemistry for scienceand engineering majors",and the other, "introductory chemistry." Prerequisitesin mathematics are generally instituted in general chemistry and some collegesmay also add chemistry and/or physics prerequisites. The trendis toward requiring the completion of secondyear high school algebra or intermediate algebrain college. Some will allow concurrent enrollment, but these are balanced by others who requirecompletion of or concurrent enrollment in trigonometry. There is a definite trendtoward requiring high school chemistry anda placement examination before theyare allowed to enroll in a chemistry course, to validate the previous chemistry and determine whether thestudent has a reasonable chance of success in general chemistry.

For introductory chemistry thy; collegemay require the completion of the first course in algebra before enrolling althoughmany colleges do not. Students enrolled in introductory chemistry include the non-science majors who electchemistry to satisfy a general education requirement, students in nursing, home economics,agriculture, physical education, and non-chemical technology curricula. Increasingly,baccalaureate nursing, homeecon- omics, and agriculture students and clinical andresearch oriented technician studentsare being placed into the general chemistrycourse. Students who fail to meet the entrancerequirements or to pass the placement test for general chemistryare often required to complete this course or one term of it before enrollingin general chemistry. Figure 1 shows the flow of students into and througha characteristic phase two chemistry program. Note the branching basedon educational goals and background or achievement and the two inputs of students for both general chemistryand introductory chemistry. The flow from introductory chemistry into general chemistryrepresents the preparatory use of the introductory course. Many collegesrequire that students receive a "C" in theintroductory course before proceeding into general chemistry.Others require a "B" since they want entering general chemistry students adequatelyprepared and don't want to penal- ize the non-science majors.

Science and Engineering GENERAL CHEMISTRY

Major ie Id of STUDENTS Study Enter the College

Non-Science Majors INTRODUCTORY CHEMISTRY Scienc and a thematic s Background ENERAL and HEMISTRY Engineering Ability?

Major Field of Enter the Study Poor College

Non-Scienc

Colleges in the second phasehave solved one major problemrelated to the general chemistry course when theyregulate entrance into the course,thereby maintaining integrity. This creates a newproblem, namely the overriding concernin the introductory course with preparationfor the general course. Whenthe faculty realizes that the chemical education needs of thehealth-related occupational groups,the non-chemical technicians, and the non-sciencemajors group are not beingproperly serviced, when the preparatory function dominates,they are nearing the thirdphase. Phase three is characterizedby a course split which splitsintroductory chemistry into two courses, entitledbeginning chemistry, primarily to preparestudents for general chemistry, and chemistry for non-sciencemajors, to serve the health-relatedoccupation- al groups, the non-chemicaltechnicians, and the liberal artsstudents. Figure 2 shows how students with inadequatepreparation move into generalchemistry through beginning chemistry. Many schools will notcompletely cut off entry to generalchemistry from the non-science majors course becausethey don't want to lose theopportunity for a student to become excited aboutchemistry or some other science oncehe's had an enthusiastic contact with chemistry. Entrancerequirements for general chemistryfrom the non-science majors course may differ fromthose from beginningchemistry, generally being higher.

71 EngineeringScience and MathematicsBackground and Science and Ability GENERAL CHEMISTRY CollegeEnterSTUDENTS the CHEMISTRYBEGINNING V Poor 1 Non-science Majors CHEMISTRYINTRODUCTORY Figure 2 - Phase three program for chemistry in the two-year colleges. colleges. The The fourth phase hasrecently developed inseveral larger two-year and faculty in many newerinstitutions creates programs idealism of the administration idealism is temperedby a which attempt to be allthings to all people.With time this with the students.Phase four is charac- realism which comes onlyfrom knocking heads in phase terized by course splittingwhich may involve any orall of the three courses three. colleges are institutinghonors type programsinto which In general chemistry some continue to maintain the they place the creamof their generalchemistry students. They chemistry for science andengineering majors. Othercolleges are re- regular level general general chemistry flecting changes in theircorresponding four-yearcolleges by splitting student majors. This might mean ageneral chemistry coursefor into two courses based on either pre- or core- chemistry, physics,mathematics and engineeringmajors with calculus general chemistry coursemight be for the biology,geology, pre-medi- quisite. The second technicians may be includedin one or the otherof cal, pre-dental, etc.majors. Chemical example of generalchem- these depending onthe level of technicianbeing trained. A third is the combination ofquantitative analysis andgeneral chemistry into istry course splitting general chemistry coursefor those a year course,at the same timeretaining the traditional who do not need thequantitative analysisT the spread in the Course splitting inbeginning chemistry appearswhen colleges realize chemistry is so great that somestudents need ability of studentsunprepared for general to enter a col- considerably more workthan others to bring them upto the level appropriate colleges have discoveredthat the generalchemistry placement lege level course. Some phase three if lower formula will also predictprobable success inbeginning chemistry in for the study. Theyhave designed beginningchemistry program cut-off scores are used pre-enrollment splits based on thisinformation and are able tocontinue using the same college with a beginningchemistry course of fourunits has added placement procedure. One week for of five units whichincludes three hours ofproblems and drill per a second course that students come inthe summer for the lesser prepared group.Another college requires that the students mustconcurrently enroll in a placement and itdifferentiates by saying chemistry or beginning problem session for thefirst part of the semesteralong with general different examples ofsplitting at the beginningchemistry level, chemistry. There are many and administration can depending upon the localsituation and thecombination the faculty agree upon. require- Course splitting in the coursefor non-science majorsresults from the differing paramedical and the non-chemicaltechnology groups; the needsof ments of the nursing and the general these two are much morespecific than those ofthe liberal arts student by the differing generaleducation requirements citizenry. This isalso strongly influenced splitting often in science of thevarious correspondingfour-year colleges. This course chemistry courses foroccupational groups such as onefor nursing and finds the creation of On occasion this other paramedicalcurricula and another fornon-chemical technicians. for individual curriculasuch as chemistry for nurses,chem- brings about chemistry courses This type of coursesplitting most istry for cosmetologists,chemistry for fire science, etc. brought to bear by the college,community, and state or pro- often is the result of pressures These persons tend to pre- fessional licensingauthorities for these occupational areas. and orientation of these courses.The health science groupswant scribe the time, content, technologies want moresolid state more organicand biochemistryand engineering related material, oxidation-reduction,metallurgy and materialscience.

73 Another trend is one which fractionates the curriculum but integrates the disciplines. Some occupational groups in some areas want physics and chemistry but will only allow time for a single course. This is so in some nursing, dental related programs, fire and police science, metals-related technologies, etc. A faculty and administration may decry and oppose these splitting trends butwhen they are dealing with state boards that license, specialized accreditingagencies that approve, and vocational educational groups that dictate what must be done for the college to receive various Federal monies, the institution often has little option.Failure of the chemistry faculty to respond to these occupational needs or requests results in the removal of such courses from the chemistry department into the occupational orvocational-technical area where they are taught by non-chemists from the occupational faculty. This poses many problems for a college chemistry program. Many descriptions of chemistry programs in the two-year colleges and recommenda- tions related to such programs have been published in publications of the AdvisoryCouncil on College Chemistry, the Two-Year College ChemistryConference of the Division of Chem- ical Education, the Improvement of Instruction Workshops of the California StateDepart- ment of Education Bureau of Junior Colleges, and the University ofFlorida-Community Col- lege Articulation-Conferences in Chemistry.To anyone interested in IntroductoryChemistry Courses in Two-Year Colleges and in examples of the developmentsdescribed earlier, I would recommend they review these publications and reports. Many colleges would like to make curricular changes inchemistry. Many should do so to be fair to their students. Problemsrelated to faculty time, facilities, space, and budgets force many to stay in their present phase. Four ways of accommodatingchanges which some colleges have found should be mentioned. First, the use of concurrent laboratory sections where thereis a low enrollment in two or more courses or laboratory sections.Students from two different courses are assigned to the same laboratory at the same time andunder the same instructor. This is possible when the administration is willing to allow separatelecture sections for each course. This technique cuts the cost of necessary low enrollment courses. Second, the analysis of courses to determinesimilarity in principles, ideas , and depth required.If enough compatibility is found they may group students intolarge lecture groups for appropriate lectureexperiments and presentation of the chemical concepts and principles.Students would also be scheduled into small discussion groups and laboratory sections in which the discussion andexperiments would be directly related to their curricular needs. Third, audio-tutorial instructional systems arebeing given serious consideration. The possibilities for the development of severalsomewhat unique packages for self-instruction under the general guidance of afaculty member are great.Postlethwaite has pioneered this in botany at Purdue and Pate and Flitcrofthave effectively applied it to chemistry at Simon Fraser University. Heider of MeramecCommunity College has an Esso Foundation grant to develop such programs in chemistryand the two campuses of Oakland Community College are completely committed tosuch programs for the whole instructional program.The audio- tutorial approach will allow a college to take careof the differing needs of small groups on an independent basis and has merit.However, an effective program of this typehas large initial costs and requires provision for constantrevision and updating.

74 Fourth, the idea of regional cooperation and planningshould be explored in the context of more effectively opening the doors of chemistry toall the students. Institutions within 20 or 30 miles of each other might agree that onecollege would offer the chemistry for nurses and another the chemistryfor technicians. Arrangements for coordinatedschedul- ing and transportation would have to be included inplanning such cooperation. In summary we find large numbers of students inthe two-year colleges whose goals and abilities are more diverse than one finds in mostfour-year colleges. Placement procedures are being utilized to screen students and place themin the chemistry program where they have a reasonable chance of success andwhere their educational needs for chemistry will be most efficiently serviced. Placement ofstudents and design of courses tends to be by majors and therefore somewhat related toabilities and student achievement. There is much concern about the integrity of the programfor the colleges desire that their students be able to flow smoothly onto their nextimmediate educational or occupational goal. There is concern about how a college can servethe chemistry needs of a diverse student body and curriculum in educationallyefficient and economically feasible ways. This concern is giving rise to new approaches inscheduling courses, designing courses, and in the utilization of autio-visuarmaterials.

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