The First Day of Class-The G.E.M. Approach Bruce G. Smith
Appleton Public Schwls Appleton. WI I am not a chemist. I am a chemistry instructor. The two professions require two distinct sets of skills. The skills of one, although useful, are not a reauirement of the other. A good chemist may ormay not make a good teacher of chem&ry. The converse is also true. A high school chemistry instructor, in particular, must be very skillful in the teaching of chemistry although he or she may not require the technical background that a skilled chemist would. One of the most important set of teaching skills required by a successful chemistry instructor are those used during the first class meeting in an introductory course in high school chemistrv. This entrv course mav. in larze Dart. determine the success k and attit;de toward chemisir< he introductory chemistry class is often the first science class elected by students. The nature of their experience in the course will affect the life-long attitude they have toward chemistry, and indeed science. I t is, therefore, of tantamount concern to all science educators and society as a whole that these students have a positive experience. The first class meeting sets the process into motion. it is h o ~ e din . the rieht direction. During this relat⪙ short of time, the instructor must attempt to set the proper tone for the course, detect misplaced individuals, lower chemistry/science anxiety, motivate, and encourage the student along with handline reauisite bookkeeping activities. One approach to meetini this challenge is what I refer to as the C.K.M. a n ~ r o a c h(Greet. ~ v a l u a i eand , Motivate). Let's look a t thegoals and somd possible methods involved in each Dart of the a~oroach. Greet: The objective here is to set a positiv~,~upportive atmosphere in the classroom setting. This should he done immediately and overtly. Many students are apprehensive about taking chemistry. They should be made to feel welcome and cared about. Meet them at the door, say "Hi," shake their bands, introduce yourself personally! In short, start them on the way to feeling part of the room, as a place to work, make mistake, try, fail, succeed, and learn. A student will learn best in such an environment. Evaluate: There is a need for the teacher upon meeting his or her students for the first time to obtain an immediate and .-~.objective "read3'on each of them. Students are a t times misDlaced in a chemistm class. either in a level below their DOtential or they may begetting in aver their heads. The longer this situation goes undetected the more frustrated hoth the student and the teacher will become. Further, the mechanics of transferring the student to a more aooro~riateclass mav become incre&ingly more difficult the ionger one waits. FO; these reasons teachers should d e v e l o ~some instrument that can be used in their classroom which &n be used to survey the students earlv in the course. as earlv as the first dav. The instrument should he simple, easy to administer and score. I t should screen for general aptitude and readiness for the study of science as opposed to a test of specific knowledge or skills. Some teachers, aware of the importance of math operations in chemistry, will use a simple math scrrening test for this purpose. A simple essay on why. they decided to take chemistry may give the teacher a sample of the students' writing and organizational skills. I have developed a cloze reading test from the course text materials to he used for the purpose of prescreening students in my chemistry classes. I have found this instrument to be most useful and reliable. In fad, in a three-year study, the test was found to be statistically valid in helping predict those students who may or may not be successful in a high school chemistry course. More information on this techniaue mav be obtained from various sources on reading or from this author. The point is that the teacher should develon some techniaue for obtaining information about potentiai chemistry students in additionUtopast ~
records andlor subjective evaluation. Both the student and the teacher will twnefit from the information. Motivate: This is without adoubt the most important part of the entire ap~roach.You have hefore vou on the first dav of class a groupof people who for the most part do not know why they took chemistry or are taking it for the wrong reasons Tell them why they took chemistry! First, however, ask yourself: Why am I teaching chemistry? Why do Ithink taking chemistry is important? The reasons may involve your love of foul smells or large explosions. They mav revolve around the importance of science in society. lierhaps the symmetry of nature is the drawing card for you. Whawver it is, tell your students why you feel it is important. Do not expert all of your students to approach the same level of enthusiasm as you on the first dav. but before vou can evrr hone that science will be important t o your students you have to convince them that it is important to vou! share with them the excitement, challenge, applications, heautv, and fun that vou see in chemistrv. This can be done with dimonstrations, hands-on inquiry o;exploration, slides, or posters. Remember that lastinr! imoressions are often made eaily. This may he the time to pill obt your best demonstration, or a simple, colorful lab exercise. You can get to the technical explanations later in the course, for right now just let them wonder! Have a set of slides made up of various classroom situations that occur throughout th' year. Show your new students that people just like them have taken chemistry before and lived. In fact they had a bit of fun. One technique that I have found successful is to read to mv classes comments made by students about the class during ihe endof-the-year evaluations. Of course, I edit them, hut at least you can show that other students have found that it is possiblk to enjoy a class that is hoth difficult and challenging. I have found that the first day of class is the day where you can hook them, get them on your side, set them up for the whole year, and, anyway, the world will not stop if you do not hand out this or collect that until day two. First things first! ~
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My First Day in a First Course in Chemistry Henry A. Bent NO* Carolina State University Raleigh. NC 27695
What am I striving to do for my students in a first course in chemistry? Increasingly I'm convinced that my major goal should be to contribute to the students' general education-to their development as observant, expressive, thoughtful, knowledgeable, and imaginative individuals. Two questions arise. Is a chemistry course an appropriate place to acauire-or to beein. or to continue to acauire--a general education? And if ci;eiistry is a good place fo; it, how does one eo about it? The hil lo son her Alfred North Whitehead hasanswered both q;estioni. "ITlhere is not one course of studv which merelv eives general culture, and another which special knowieige," writes Whitehead in "The Aims of Education." "The subjects pursued for the sake of a general education," continues Whitehead, "are suecia1 subjects sueciallv studied" (emnhasis added). ~. A path to general education is chemistry deeply studied. 'I'he Tao is hidden in the depths of all things. 'I'he depths of chemistry lie in chemical transformations descrihed as chemisrs descrihe them and imagined it* chemists imagine them. Huth the things described and the things imagined can be-with Bohr, one would say must be-described in ordinary language. Briefly put, what I am striving for for my students is chemical literacy. When they see, e.g., a demonstration of
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Volume 62 Number 7 July 1965
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sodium reacting with water, I want them to be able t o write something like this: A soft, silvery, metallic-looking solid dropped into a nonconduct-
ing, colorless, phenolthalein-spiked liquid balls up into a spherical shaoe. . . skitters about on the surface of the water as if .iet-oro. pelled, and produces a colorless, odorless, less-dense-than-air, highly flammable gas and a pink, electrically conducting solution, and disappears. And I want them to understand that such a statement corresponds to this chemical expression: 2Na(c)+ 2Hz0(1) = Hz(g) + 2Na+(aq)+ 20H-(aq) + heat And, finally I want my students to see, eventually, that the chemical expression above corresponds to such statements as those below.
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Production of hydrogen from action of an active Group I metal on water. Formation of sodium hydroxide from sodium and water. Destruction of waste sodium with water. Drying of hydrocarbons with sodium wire. Displacement ofhydrogen from water by sodium. Reduction of water by sodium. Oxidation of sodium by water. Protonation of sodium's valence electrons by water molecules yielding doubly protonated electron-pairs(H-H, i.e. Hz). Deprotonation of water molecules by sodium's valence electrons, yielding deprotonated water molecules (OH-). Electron transfer from metallic sodium to oxygenated hydrogen, yielding Na+, Hz, and OH-
Such literacy is not quickly acquired. I t requires learning new words for new sensory experiences. It's like learning a first Howhid we learn our first language? Not from books and lectures. We learn a first lanmagc by heing around people who use the language seriously, for rial-life purposes. Andit helps if they point and tell ~ o - h estudents l~ become chemically literate, we need t o show students what chemists can show, sav to students what chemists can say, write for students what ihemists can write, and describe for students what chemists imagine. Providing students with those experiences is the alphaand omegaof my beginning course in chemistry, beginning the first day. I ask mvself. . . What can I show? Oulv then do I consider, What can I say? The opposite procedure, which I followed for many years, of deciding f i t on a syllabus and then wondering what demonstrations (if any) I might do, puts the cart before the horse. It's jobbing backwards. It's jumping to conclusions before the facts are in. As Lavoisier advises in the preface of his "Elements of Chemistrv." .. "lIln . . commencing the study of a physical science, we ought t o form no idea but what i s a necessary consequence, and immedite effect, of an experiment or observation." Lavoisier's Rule of Restraint is not easy t o adhere to. But it makes for a good game. The game's called Science. Anything less, in Robert Frost's words, "is like playing tennis with the net down." My course is designed around simple, short, safe, striking, and inexpensive lecture experiments. Chiefly we exhibit pure substances. heat nure substances.. droo ..nure substances into pure substances, and record in our notebooks what we've done, what we've seen. what chemists sav. -.what chemists write. and what chemists imagine. On Day 1 we might heft and drop wood and lead bricks; strike a match; drop dry ice into water; spray water into burning paraffin; heat iodine, sugar, or ammonium dichromate; immerse burning magnesium in steam and carbon dioxide; allow nitric acid to act on copper. I t doesn't matter where one starts. We can reach the center from any point on the compass. The previous speaker has left us iodine in a flask on a hot 804
Journal of Chemical Education
plate. That is a pretty color-one of the prettiest in chemistry. Let's add some water. (Let's hope we don't crack the flask). Ah! There's the color of iodine in water. Brown. It's brown, also, in alcohol and acetone and ether and amines. But it's violet-the vapor's beautiful violet-in hydrocarbons and chlorinated hvdrocarbons. I t doesn't interact with those solvents. You don't need a spectrometer t o see that. But the iodine molecules do interact with oxygen- and nitronen-containing solvents-indeed with any b& solvent. ~beaolvents' lone pairs attack the back sides of Iodine-Iodine bonds. It's the first step of an S N displacement ~ on iodine. With hydroxide ion the interaction goes all the way to a reaction. The case for chlorine is familiar: OH- CI-C1= HOCl + C1-. But now a paradox: Add one of the "violet solvents," for example heptane, to the aqueous solution, and shake. (Oil and water don't mix.) Surprise! The iodine molecules leave the water molecules with which thev were interactine and end UD in the inert hydrocarbon layer. That's counter-intuitive. Or is it? It's not that iodine molecules don't "want" to interact with water molecules. They do. But water molecules, given a chance, would prefer to interact with water molecules, via hydrogen bonding. The iodine molecules, like hydrocarbon molecules, are saueezed into the hvdrocarbon nhase bv hvdroeen-bond formation in the aqueous phase. 1n bioche&ry, &at effect is called "hydrophobic bonding." But we can get the iodine back into the aqueous phase hy adding potassium iodide. I t is soluble in water but insoluble in hydrocarbons. (Like dissolves in like, and water is salt-like. Its molecules are dipolar.) Formed is the triiodide ion. With alcohol as a solvent, we'd have a tincture of iodine. You see what happens. As individual experiments are woven into a whole, the; gain power to represent the whole, and transitions to the whole become possible from any experiment. Gradually students acquire new mental images and a new language for describing and thinking about the world around them. They become more observant, more expressive, more thoughtful, more knowledgeable, and more imaginative individuals. Becoming chemically literate, they acquire a general education. There's a good education for good living in chemistry. That's what I try to suggest the first day-and every day-in a first course in chemistry.
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My First Day of Class-is a Typical Class Day David W. Brooks University d Nebraska, Lincoln. NE 68588
The first dav of class has alwaw worried m+it is the only class day during which I am likeiy to have "butterflies in my stomach." If the dav means so much to me, there is a nagging -.. feeling that i t mustmean alot to my students. Analysis shows that my worry is usually greater than is theirs. In past years, I have tried all sorts of things to involve students during the first day of class. At one time, I greeted each student a t the classroom door with a handshake, an event that was never noted on over 1,000free-recall student evaluations at the end of the semester. Later, I had students stand up and introduce themselves to the whole class, or break into small groups and introduce themselves to one another in the group. Flashy demonstrations, jokes socomy as to he memorable, and other snecial events seemed more noted hv me than bv them. When you ask students about the& classes duiing the first week, they will tell you how they feel. However, most of them can tell you how they feel before the first class session meets, especially if it is a chemistry class. That opinion is formed-at the latest-in the dormitories on the days before classes start. Nothine sets the tone for the first dav of a college chemistrv class b e k r than to have a high school chemistgteacher say,
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