Avoiding poor morale - Journal of Chemical Education (ACS

Students often ask their chemistry instructors questions that the instructor cannot answer. Keywords (Audience):. High School / Introductory Chemistry...
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JOHN H. WOODBURN, PhD 9208 Le Velle Drwe Chevy Chase, Maryland 20015

Avoiding Poor Morale This column has suggested that we take new looks a t our :lassroom formats and instructional procedures. And rightly 30. Our demonstrations and lab exercises must come off imoothlv. Our outside readine assienmeuts must sup~lement .. md add interest to course content. Our tests and examinations must give us valid and reliable estimates of student achievement. In fact, each classroom activity has much to do with our lavine eood versus bad davs. . . with our being- either elated or iepressed by our roles as teachers. When we listen to the grumbling in faculty coffeeshops, the xigins of our discontent range far and wide. "Front office" iecisions draw much criticism. T o try to trace the origins of thrsr decisions to the community or societal forces wh~chget lo the decision makers, however, ran take us into highly contested d o m a i n d o m a i n s where gamemanship involves ethics and strategies quite inconsistent with the spirit, logic, and sthics of science. Amateurs fare badly but for those people who Ire brave enough to joust with giant windmills, the rewards loom large. Others of us will gain more by asking ourselves the simple mestion: Whv do we have eood versus bad davs in our classrooms and laboratories? ~ ? l aare t the immediate precursors 3f our feelines of success versus failure. satisfaction versus Frustration? How many of these precursors can we manipulate, manaee. - . or control? These auestions must he answered per3onally. This column can only suggest possible answers. Not being able to come up with good answers to our stulents' questions can be a most deadly attack on a teacher's lense of adequacy. Even a slight jiggling of our positive selfimage can unleash a chain of events leading to a bad day. In many situations, our only source of commendation and reinforcement is the reactions of our students to our teaching. Their looks of satisfaction when we know the answers to their questinns are powertill ratalysts. There is something about chemistry as a sch(wlaubjert that rppears ro generate a large r o l ~ ~ mofnquestions tearhers are not ready to answer- -questioni our students cannot find noswers to in typical textbooks-questions even the most sxperienced teacher knows will not be answered to the complete satisfaction of all but a select few of our students. Should this column move toward trying to solve this can't-answer-their-auestions~ r o b l e m ?Can this Journal bring the resources inherent in the profession and industry of chemistry to bear on solving this problem? Might we look forward to a chemistry teacher's cumulatiue handbook containing an increasingly complete listing of questions students xsk together with accurate answers contributed by competent chemists who acceDt the challenge . of. communicating to naive students? Here are some examples of the kinds of questions that have been known to throw teachers off their stride. A standard lab exercise has students synthesize iron or copper sultide to pnwidp practice in determining empirical lurmulas. llsually thingsgo well until we reach thestep where we determine the whole number ratio of metal to sulfur atoms.

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398 / Journal of Chemical Education

Here is where "wrong" questions become a threat. True, we can fend them off by evoking "experimental error," "significant figures," or similar tactics. But what are we to do when a student asks, "The chart shows irou with valence I1 or 111. Which valence should irou have in the iron sulfide we made?" Litmus paper touched with a drop of vinegar shows pink color. The same test strip touched with a drop of drain cleaner solution shows blue. But what is the third grade teacher to do when kids want to know why this happens? High school chemistry teachers can field such a question by visiting such concepts as proton donor versus proton acceptors. But what are they to do when students want to know why the presence or absence of protons affects the color of a substance? To see a gloking splint burst into flame in a test tube where lead dioxide is being heated can entertain eeneral science studenrs. Hut the te&herSsday can take u hdh huunce when kids want ro knuw why theoxygen in the test tuhedoes thing5 that aren'r done hy the oxygen in the air. '1'0 reinforce thesafetv rule that rewires sulfuric acid to be added to water and notiice versa, weoften explain the temperature rise that accompanies this reaction. But how many of us hope the bell will ring before our students ask about the temperature changes which accompany the solution of ammonium chloride? The thermal decompositi'on of ammonium dichromate can bring down the house with or without the stage prop of a papier-mache volcanic cone. But students can spoil our fun if they demand a full analysis of the thermodynamics of this reaction. T o see a beaker brimful with water in which an ice cube is floating fail to overflow as the ice melts can generate valuable auestions. But manv of us dread those auestions which call for a clear and valid description of the factors which accomDanv . " the chaneine densitv of water as it nears the freezingtemperature. T o tease our students hv adding water to the residue from heating hydrous copper &fate while the crucible is resting in the palm of their hands is a fun way to emphasize the role of energy in hydration reactions. But our students can even the score when they demand an explanation of what happens when water is added to "anhydrous" potassium chromium sulfate. T o return to our original theme, if the inability to answer our students' questions is a constant threat to our morale, does a handhook of accurate and valid answers oromise a solution? How often can teachers back away from their students' questions without risking the rapport with or respect of their students? How often can we say, "That's a good question but you will have to wait until we are ready to answer it?" Is it not true that each question our students ask that we can answer to their satisfaction (and ours) takes us one step closer to having a good day? The time has come to shape up the future of this column. Should we move toward accumulating a collection of valid and accurate answers to those troublesome questions our students ask? Can the answers be expressed in language we can all understand?