Getting Students To Profit from Chemistry Clifford LeRoy Schrader Dover High School, Dover, OH 44622 T o make a profit requires a product that is mutually heneficial t o hoth the buyer and the seller. The positive perceptions created by a persuasive sales pitch must be followed by the acquisition of something of value. Profit can he used as a metaphor for teaching and learning chemistry. Students who acquire thinking skills by solving problems profit from chemistry, and, if they also make money, the double meaning of the title is apparent. Students in my chemistry class found that learning chemistry was exciting, enjoyable, and ~rofitahlein hoth senses. Solving real-world chemical problems is an exciting application of ~ r i n c i ~ llearned es with textbook abstractions. The students in my chemistry classes started a chemical company, and the problem was how to maximize their profit. The chemical we bought and sold was no abstraction. Profit was not a dirty word. Teachlng-The Never-Endlng Challenge . It has been my good fortune to find a career as a teacher. I have enjoyed teaching. That is the one constant of my pro. fessional career. I am still learnine how to desien lessons that will enable every student t o learnchemistry. students show meat variation in achievement deoendine on their intellectual capacity, their predilections, and the support and encouragement of their parents. Thanks to Dudley Herron, I have a much better understanding of the differences among students and how those differences may he recognized. The task of developing teaching strategies that will help students construct a meaningful view of the chemical world that is consistent with experimental evidence is challenging. Toward this end, I usually introduce chemical concepts with demonstrations or student experiments rather than lecture. I t is easy to focus on the chemical concepts that students should learn and understand. We need to ask why a student should want or need to learn each concept. As a beginning teacher I taught what I had been taught in college. Although I had some eood teachine models. it took me some time to realize that goals were quite different from the goals of college professors. Their goal is to prepare students for a career in chemistry or a related science. Most of my student will not pursue a career in science or a related field. Therefore, my goal is t o teach students the nature of science, thinking and problem solving skills, and the relationship of science to their lives. At first I only knew how to focus on what I thought were the important chemical concepts. As I learned more chemistry, I became able t o make effective connections between concepts studied in the laboratory and classroom and the everyday life of the students. I gradually learned how to provide examples of applications of chemical processes in the everyday experience of my students.
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my
A Lucky Accident
As president-elect of the Wooster Section of the American Chemical Society I was responsible for arranging the proThis article is baaed on the James Bryant Conant Award Lecture presented a t the Dallas ACS Meeting in spring 1989. 886
Journal of Chemical Education
grams for our meetings. I asked a friend of 25 years, Robert Cohen, t o talk about his experiences in the chemical industry. The talk was so interesting that I asked him to repeat it to my chemistry students. My students learned how a research chemist started a chemical company with $3,000.00 and hecame a millionaire. Cohen described how he purchased 3,000 barrels of government-surplus chlorinated hydrocarbons for $1per barrel. He knew that chlorinated hydrocarbons were used in highpressure lubricants. One important government condition of the sale was that the material had to be moved from the eovernment storehouse within 30 davs. A buildine was renti d and the drums were shipped to dover, Ohio. '' He heean hv selline the material in 5-eal buckets from the trunk oflhis car. ~ o o he n had enough c&omers to justify a loan, rent a building, and to hire employees to purify, package, and ship the product. By the time he sold all of the 3,000 drums of material, he calculated that he could buy raw hvdrocarhons and chlorine gas and manufacture an even better product. He invested in capital equipment, research, and continued to improve his products Ad expand his business. After 25 years his company was well established and profitable enoueh to attract an offer of a buv-out hv an international company. Hesold thechemical company he hadstarted for $3.000 to a laree corooration for $3.000.000.00. Mv studen& &ere quite impressed with this aicbunt. ~ e c o m i i ~ a millionaire through hard work is a respected achievement. Tlmlng Is Important A few weeks after Cohen's talk to my students, an official a t a local steel company called me for advice in the disposal of zinc sulfate monohydrate. I found that zinc sulfate is not presently classified as a hazardous substance by the environmental protection agency. There are stringent restrictions on the disposal of all chemical wastes. A waste chemical, even when disposed of by a contractor, remains the responsihility of the company that generated the waste. If that suhstance is dis~osedof i m ~ r o ~ e ror l vlater classified as a hazardous che&ical the genmakngcompany remains liable. The ~ u r ~ oofs ethese regulations is to motect the environment for eieryone. A receit local environmental controversy that was caused by improper disposal of a waste chemical, believed a t the time to he completely harmless, is an illustration of the rationale for the EPA laws. Trichloroethylene, (TCE), C2H3C4, is used as industrial degreaser because i t is stable, nonflammable, nontoxic, and inexpensive. When the TCE was spent (no longer capable of degreasing parts effectively), i t was disposed of by simply dumoine i t on the eround. Two industrial users of TCE are locaied iery close 6 the wells that supply our water. Recent studies indicate that TCE is a potential human carcinogen. Routine testing of the water detected up to 500 ppb of TCE in the citv well water. More than 100 D D of~ TCE have likelv been present in the water for more than 30 years, but thk amount was too small to detect until recently. Advances in analytical techniques now make i t possible to detect TCE in the ppb range. EPA regulations required the construction of aeration towers costing over $550,000, to reduce the TCE level to an acceptable 5 ppb. All this trouble and expense for a chemical
that was once helieved to he innocuous. The TCE incident illustrates the rationale for regulations which assign responnihilitv to eenerator of the chemical waste. This nroce.. the ~-~~" dure prevents companies from using fly-by-night waste disposal operators who practice "midnight dumping" and then declare bankruptcy t o evade responsibility for repairing the environmental damage. Instruments that allow more sensitive detection, increased knowledee of toxicologv, the NIMBY (not in mv hack yard) syndrome, and the&oliferation of lawyers are some of the factors related to changes in the way chemicals are disposed. All of these factors have increased the cost of disposal.
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Chemlcal Lovers Company, Ltd.
I discussed the disposal problems associated with zinc sulfate with mv students. It is unfortunate that this compound, which required time, energy, and money to purify, is eoine to be an additional exnense to the steel comDanv. If Zumied into a land fill, n o i only will a potential?; uskful chemical be wasted, the company will have to worry about future liability. The alternative is to continue to store the zinc sulfate a t the plant. The class answer t o the problem was to start a chemical company, buy the zinc sulfate, and find ause for it. This was the beginning of the C. L. Company, Ltd. (The C. L. was for chemical lovers.) We bought the 5,000 kg of zinc sulfate monohydrate from the company for $1.00. Because they sold the zinc sulfate to us, it was classified as a product and the steel company had no further responsibility for it. We solved their problem. We issued 50 shares of stock a t $20.00 each to provide working capital. A t our first shareholders meeting we elected a president, vice-president, comptoller, secretary, sales manager, production supervisor, legal affairs liaison, labor foreman, research director, and quality control chief. Each of these elected officials recmited shareholders t o complete their staff. There was work enough for evervone. With the heln of two former students who are now lawyers we filed incorporation .o m e n with thestateofOhio. Weeot afirst-handlookat red tape! Incorporation was necessaryfor us to do business, and i t was our largest single exDense. We needed-to f i n d a place to store the substance until we could find a market for it. One of our shareholders had a barn he was willing to let us use for a small rent. Moving the chemical to our place of business was complicated. The selling company was fearful of liability for injury to our workers and their subsequent liability. They would not allow us on their property until we were able to obtain Workman's Compensation Insurance. The State of Ohio issued us the insurance quickly and a t a modest cost. Our production manager arranged for a truck and dust masks to prevent inhalation of the zinc sulfate monohvdrate by our workers. Our labor foreman issued a Eall for workers to move the 15,000kg of zinc sulfate monohydrate to our warehouse. The material was packaged in plastic-lined barrels that weighed up to 200 kg. Not all the stockholders were able to help with moving. There were a variety of valid reasons such as a track meet, a band contest, a tournament baseball game, or a lack of interest in manual labor. Quite a lot of work was required t o package and move the substance, and i t did not seem fair to have all shareholders benefit from the labor of the few who did work. At a stockholders meeting we decided to pay the laborers. The stockholders who did not plan to work suggested we nav the lahorers $l.OO/h. Reducing the labor cost would &ximize their profit. The stockhkders who planned to work asked to be paid $10.00/h. The workers would then earn a salary up front, plus their eventual share of the profits. Some important economic lessons were learned by all, ~
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and we finally settled on a wage of $3.00/h. This was the smallest pay rate that would attract enough workers. A 250% Proflt The next task was selline our nroduct. I had worked for several years in the research and development section of an electroplating company, and I had contacts that were useful in identifying potential customers. The going rate for electroplating-grade zinc sulfate monohydrate was $0.66/kg. I t was clear that we could not sell our material as electroplating grade because of contamination with dust. dirt, and oil due to years of neglect. Impurities are one of the scourges of the electroplating process. Dirt produces bumps on the surfaces of the plated product. Other impurities like oil cause other deleterious effects. The result for the electroplating company is ruined material, used up chemicals and work pieces, energy, and labor, and no salable product. We could not filter 15,000 kg of zinc sulfate with filter naoer and Buchner funnels. Even if we could obtain an inchtrial filter press or a rotating drum filter, we would still need substantial labor and an environmentallv acce~table way t o dispose of our effluent. Our research team learned that zinc is one of the microtrace elements necessary in soil for proper plant growth. Agriculture is Ohio's biggest industry so there was a large potential market. Zinc is not routinely added to commercial fertilizers. Application of zinc may be recommended as a treatment toyfarmer as a remedy for crop failure caused by azinc deficiency. I knew aparent who worked for the agriculture denartment samnline the soil in Ohio. From him we learned'which counties inU0hiohad soil that was zinc deficient. Another former student was completing a PhD in agronomy a t The Ohio State University, and he gave me the name of the Ohio State University expert in microtrace elements in the soil. We obtained the recommended rate of application of zinc sulfate per acre for zinc-deficient soil. Our sales manager used this information to devise a sales campaign to market the material. The students knew that you must have a good product. They also learned that you will not succeed, no matter how good your product, if you do not have an effective marketing strategy. The zinc sulfate monohvdrate (which in the humid Ohio climate wan becominga tr&drate) wassold toa small fertilizer company near us. For the discount mice of %0.22/kethev sent a tiuck and workers to pick it up. We sent them & invoice and a material safety data sheet and received prompt payment. A former student, who is a certified professional accountant, helped us complete the forms required to liquidate our corporation. Our shareholders received a 250% profit on their investment.
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Radon Raiders
The Radon Raiders were established by the advanced chemistrv class of Dover HiehSchoolon October 1.1988. We . were stu&ing a unit on n;clear chemistry when the EPA announced they were advising everyone to have their home tested for radon. Homeowners can test their homes for radon in several ways. Many stores sell radon test kits. The kit contains a canister of activated charcoal, which adsorbs radon gas. One or two weeks of exposure is usually required to obtain a representative measurement by this method. The canister is sealed and sent to a laboratory. Since the half-life of radon222 is .3.8 days, the laboratory detects and measures the daughter products and then calculates the average amount of radon-222 that was present a t the time of exposure. A second method involves a direct measurement usine a Geiger-counter-type instrument. Each radioactive isotope gives off radiation with a characteristic energy. Our instru~~
Volume 67
Number 8 August 1990
887
Nuclear Equations Halflife 4.5 bllllon years 24 days 6.75 h 250 mllllon years 80 thowand years 1602 years 3.8 days 3.05 min 26.8 min 19.7 mi" 40 9 20.4 years 5.0 days 138 days
--
Method of Decay
+ $?h ;?h !" +,;?pa ;:?a + :Tu U: ; -:He + ;;am :HB
;:%I
-- ++ -- +++ -I,* + -- ++ - ++ !,e
r ; T h
: ~ e ;:%a :He ::2Rn :EZRn -:He :P 'o :?PO :He :;P 'b !,w :j461 ::'~b ::%I :P 'O :P 'o :He :i0Pb !,e ::061 :;%I !,e :P 'O P P o -:He :Ypb
ment was designed to respond and record only the alpha radiation from radon-222. This method allows hoth an instantaneous measurement and an accumulated average over any period of time desired. Longer time periods result in st&tically more precise and reliahle m&surements. Our usual exposure time was 20-22 h. We made repeated measurements with the same and different instruments and found the answer did not vary more than 10%. Our sales nresentation stressed the benefits of testine. There is greai variation in the radon content of homes. ~ h variation mav be due to differences in home construction. location, type of building materials used, origin of the build: ing materials, date of construction, how effectively the home is sealed, etc. It is necessary to have precise knowledge of the radon level in the home beforeattempting remediation. Radon levels varv widelv. The March 27.1989. issue of Chemical and ~ n g i n e e r i n g ~ e w reported s high radon concentrations in Montclair, New Jersey. In some states aradon test is required before selling a home. The cost of testine is moderate. usuallv less than $30.00. For homes with readTngs of 100 p ~ i orn less, the radon level can be reduced to an acceptable level bv the home owner for less than $100.00. A pn)t.e&)nal will us;ally charge leas than $1.000.00 for the same iob, which consists of sealine cracks and porous materials. For measurements of more &an 100 p C i n the cost will vary according to the severity of the problem. In addition to sealing the installation of a venting system may be advisable. The advanced chemistry class of Dover High School had four goals: 1. to test homes for radon inexpensively
to educate the general public to the characteristics,risks, and the effeds of radiation 3. to conduct research to determine which type of home or location is highest in risk 4. to make a profit 2.
688
T o accomplish these objectives the students were required tostudv and develon their understandine of nuclear chemistry, develop comm&ication skills, design a research study and a data collection instrument. and to orepare.. . nractice. and use a protocol to ensure standardi~edtesiin~. Concomitant knowledge acquired by the students included the processes involved in the formation of a company. It was necessary to develop a price structure for the radon testing fee, record management, financial policies, sales, product information, quality control, and job management. Each student bought one or more $25 shares to provide the funds required for the initial investment. The students prepared the research instrument, the information paper to be handed to customers, scheduled appointments, and handled all visits. In cases where high levels of radon were detected, the students exercised judgement, and when appropriate referred the customer to a professional for further consultation. Radon Raiders results for Dover, Ohio:
Journal of Chemical Education
46% with a reading less than the EPA standard of 4 pCiL 44% from 4 to 10 pCiL
8%from 10 to 20 pCiL 2%from 20 to 100 pCiL 0%greater than 100 pCiL
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Chance Favors the Prepared Mind As a teacher my goal for these activities was to provide experiences that would show students why they should learn something about chemistry. Chemistry students should learn to solve problems, design experiments, control variables, examine consequences, analyze experimental data, and evaluate the exnerimental results. These processes were identified by B. S. Bloom as the highest levels of cognitive thought. The formation of both chemical ~ompanie~involved applications chemistry and required the use of important thinking skills. As a chemistry teacher I have three main goals. First, I want t o teach students how to think, solve problems, and to learn to use their minds. Second. I want to produce students who understand science concepts so they can make intellieent decisions on nuhlic issues. Thev will nartici~atein risk assessment of environmental issues. Environmental prohlems are comnlex and many factors must he considered. Finally, I want to produce &dents who want t o he a part of the decision making process on nublic issues because only then can a democraiic society succeed. These goals in hoth the affective and cognitive domain were supported, fostered, and enhanced by the formation of the chemical companies. In addition, each student received a 250% return on his or her investment. My students profited from chemistry and I have profited from the opportunity to teach chemistry with a different slant when the lucky concatenation of events occurred.
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