Gerard P. Baruch Lackey H ~ g hSchool lndlan Head. M~ 20640 and Lyle 0. Malotky
Teaching Chemistry to High School Students in a Government Laboratory
Chemist
Naval Explos~onOrdmance Dtsposal Facrllty Indian Head. MD 20640
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In the Fall of 1978, the Naval EOD Facility established a co-operative program with the Charles County Maryland Board of Education which allowed pre-selected high school students use of the chemical instrumentation laboratory a t the Naval Facility on a weekly basis. This program offered instruction in gas and thin layer chromatography, visible and IR-spectrometry, the electric balance, and the differential scanning calorimeter. The results of the nroeram are favorable. Students gained a respect for lahoratorysafety and the time needed tocarry out research. Thev designed a research proiect, and utilized chromatography i d sp&trometry techn:lqu& in carrying out the research. They met professional chemists and engineers during the course-of theprogram and gained insight into careers in the sciences not provided in the classroom. In an effort to help other educators utilize available facilities, we will discuss some of the governmental regulations zovernine secondarv school students in industrial laboratories. " The advantages such a program presents, as well as the disadvantaees, will also be nresented. The proeram as develoned will be &scribed in its'entirety, includingobjectives o f t h e program, selection of participants, actual participation, actual experiments performed, and estimates of time and material required. Finally, recommendations for future experiments and topics, as will as brief overview of the accomplishments of the students, will be presented. Obieciive of the Program -
The objective of this program has as its broad purpose the enhancement of the existine educational . proeram in the sec. ondary schools. Specific objectives were to expose students to good laboratob techniques and safetypractices to tesch studentshow to use instruinentationnot normally available on a secondarv school level r u teach students t h babir ~ practicer of good research design r o nllw rtudmta the opporrunity for dialogue with proiessional scientists togivestudents theopportunity togain insight into the careersof professional scientists by observing the types of activities which occur in their everyday professionallife. Selection of Partici~ants Pnrticipatiun in this progrnm was limited to students who had completed one vwr of hieh school chemistrv and u,howere currentl; enrolled-or who i a d completed a second year of chemistry. Particination was voluntary and no one was excluded who met the above criteria. o i l y six students were allowed at a time in the laboratory so as to guarantee that all would receive adequate instruction. Time was allotted in the prog,ram for other students a t the high school who were involved in project work and desired to use instruments a t the facility but who were not part of the chemistry program. These students could use the facility during the weeks in which less than six of the regular students were working.
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Program Description The program was divided into three sections. The first was a mini-workshon on lahoratorv safetv and research desien. This was followe'd by an introdukory ekposure to the availahe instruments and finallv the on~ortimitvto do a science nroiect utilizing one or more bf the &rumeks.
In the initial meeting, students were introduced to personnel a t the hast site and received a brief oveniew of the type of work in which the facility was engaged. Under the guidance of the chemist, Dr. Lyle Malotky, and the high school chemistry teacher, Dr. Gerard Baruch, some of the hazards of exposure to chemicals were discussed and appropriate safety regulations and rules were established. The safety equipment in the laboratory was then located and, where appropriate, was demonstrated. In the next meeting, the technique of pipeting was shown, and concentration calculations using a volumetric flask were taught. The necessity of keeping records was emphasized, and each student was is- S sued a laboratory notebook for this purpose. E The second stage introduced students to the instruments. In order to get a maximum number of students involved in the heginning,kudents worked in pairs. They began with eithei the electric balance, oscillosco~e-sienaleenerator. or thermocouple-strip-chak recorders. he students rotated to a different instrument as time permitted. Students using the electricbalance were taught basic procedures of operation. The masses of different coins was measured as a mini-exneriment which helned students become proficient in the us; of the balance and iemoustrated to them variables nresent with a sensitive balance. Students learned how air currents affect balance movement, the limits of precision and accuracy of the halance, and the correct operational procedure for minimizing wear on the moving parts of this instrument. Students who wed the ascillosn)pe-signalgenerator system learned how to correctly position and attenuate a signal so that i t would appear on t h e screen of scope in a way in which meaningful data such as frequency and amplitude could he rend. Students measured the amplitude of the penks produced as they sang into a small microphone, by an accelerometer, l)y the voltaee of several batteries. and finallv the freuuencv .of tones proiuced by a signal generator. In the later experiment, students were able to coordinate the readines on the scone with those on the signal generator. Students who o ~ e r a t e dthe thermocou~le-dieital thermometer-stripchart recorder system were ahle to coordinate the temr~eruturereadings on the digital thermometer with the graphic2 data on the strip-chart r&rder. Since the students are very familiar with temperature readings, the only new concept introduced was voltage measurement, thus making comprehension of this technique much easier. In this experiment, students first measured the temperature of various samples of water using the thermocouple which was connected to the strip-chart recorder. Utilizine the nen and . oosition . attenuation readings, students n u l i measure rhe milli\wlt oumut of the recurder and, from tables. could determine the temperature. They would then confirm this reading using a digital thermometer. After these introductory experiments, students performed longer and more involved experiments utilizing the techniques of chromatography and spectrometry. In thin-layer chromatography, students bad the task of separating a mixture of dyes. During the course of the experiment, students were taught how to prepare and condition chromatographic plates
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Presented at the 178th National ACS Convention, Washington,
D.C.,September 12.1979. Volume 57, Number 5, May 1980 / 369
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with silica gel and alumina. This was followed with instruction in swttine techniaues and solvent selection. These techniaues were later used by students toseparatr the pigments in chloroohvll . - and identifv the dves in various fond oroductli. Gas chromatography was the second type of chromatographic technique applied. Students separated a mixture of organic solvents using a Perkin-Elmer 39208 Gas Chromatograph utilizing hoth a strip chart and Perkin-Elmer M-1 Computing Integrator. Students had to find how many components were in the mixture and the amounts of each of the components. In a later project, the ingredients in a perfume were compared with the respective cologne as to the number, the similarity, and the amounts of each ingredient. Spectrometry experiments covered visible, ultraviolet, and infrared reeions. Students beean hv measurine absorhance as a function of the wavelengthhf light for given &utions. For the UV-visible spectrometer, copper sulfate and potassium permanganate were the most frequently used. In several cases, the different dyes separated in the TLC experiment were also redissolved and measured. Students used a Beckman 25 combination UV-visible spectrometer with digital readout and recorder. At least an hour of introduction was given on operation of the instrument. After becoming familiar with the instrument. students olotted the ahsorbance versus wavelength to determine the position of maximum absorbance. Students then used standard solutions as a reference and constructed a Beer's law plot, or used the instrument directly to obtain the concentration of an unknown solution. This spectrophotometer was used for two science projects of note. In one, the aspirin in cold remedies was complexed with an iron(II1) solution and the concentration of the resulting complex (which is light purple) was measured using the visible region. In another experiment, the amount of caffeine in different coffee samples was determined by extracting the coffee in a soxlet extractor, isolating the caffeine, and measuring its UV ahsorhance. At the end of the program, time was spent on the infrared spectrometer. Using a Beckman Acculab B, students measured the absorbance spectra of several imknown compounds and compared this with Aldrich reference spectra. The infrared spectrometer was used again in the final class experiment assigned a t the high school, where students had to separate a mixture containing acid, basic, and neutral organic comoounds and identifv each comnonent. Since both the unknown acid and the hasic henziyl derivative are solids, students relied on meltine ~ o i ntechnioues t for their identification. However, the nexral compounds were run on the infrared spectrometer, and samples of the spectra were given to every class member. From these, they could identify the final component of the mixture of unknowns. Number of Students Served
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Student visits were tabulated bv usine a lor" which students signed and indicated the specific activity in which they engaged during the visit. Overall, there were 59 student visits during the 14 weeks of the program. These visits represent 13 different students working in the program with an average of 4 students per day. Dr. Baruch logged an additional 5 visits to organize experiments and collected instrumental data for samples used at the high school. For example, IR spectra on unknown organic compounds were gathered and given to the students back at the hieh as a nart of their " school to analvze " laboratory investigations. ~~
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Time and Material Requests
The program, as presently run, requires a minimum of 2 hr a t least one day a week a t the host institution. Ideally, this could occur toward the end of the work day and after school so that there is a minimum disruption in hoth the educational program and on the cooperating institution. Since the sponsorioe institution is a eovernment aeencvand manv workers " wereonly required to work to 3 1 5 pm (according to the flextime standards). the selection of the late afternoon was verv feasible. 370 1 Journal of Chemical Education
In terms of support personnel needed to run the program, the minimum needed for each visit was two; one by the host institution, and one on the part of the public school. The type of personnel needed depends on the number of previous visits students have made and the projects worked on. No special equipment, other than that available a t the site facility, was needed. Chemicals which were needed, hut not a p a r t ofthe inventory of the Navy, were supplied by the high school. Students were required to supply their own safety goggles which could be purchased or lent from the high school. Results of the Program
Many results of enrichment promams such as these will not be evident for several years, whenstudents report back from college on how the experience affected their careers and college coursework. However, in terms of the objectives of the Program, the following can be reported. Students who participated in this program always stood out as the most safety conscious in the high school. Greater concern for washing elassware. keeoine . .. a clean work area. and organizing onr'i lnhoratury cal~inetwere evident. Students requesml yoggles ii the instructor iniled to unlock the cabinet where the;&re stored. Afew students even purchased their own. Overall, the safety aspect of the program was a suc. . cess. Students learned how to use instrumentation and felt comfortable with graphical data output on strip-chart recorders. They were able to coordinate the axis on the recorder oaper with the settines on the strio-chart recorder and instrument. Generally, all students in the program had some experience with the electric balance, the UV and visible spectrometer, the gas chromatograph in conjunction with the integrator, and the IR spectrometer. Students were familiar with-the general prohle& which each instrument could re~
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Students received some help in thinking out and designing their own projects. In several cases, the chief chemist tank time oul to go over each experiment and discuss the data which needed to be taken. Sweral students wtw able toself-initiate their own goals students had the opportunity for dialogue with the professional scientists a t the facility. From time to time, chemical engineers, electrical engineers, technicians, and computer programmers assisted in the instruction. The students seem to enjoy this contact, and it made a career as a scientist much more tang~hle.It is the heir approach I have seen litr makine young ad& realize that scien&s are people and that a career in science is within their grasp with hard work and dedicatlon. Along with these results, were the awards bestowed upon the students when they exhibited their projects in science fairs. In general, these projects were much better designed, more carefully thought out, and much more creative than in the past years. Students who were in the program received all awards in the local science fair. three out of five of the chemistry awards at the county fair, and one of the participants finished third in chemistry at the tour-countv reeional fair. In addition, two of these students were selected in summer research programs, one program located at the Department of Agriculture and the other at Fort Deterick. This is the first summer in which area students have elected to participate in these programs, which indicates the influence which this cooperative program has for further science involvement. Furthermore, it will give these students added opportunities to gain needed scholarship money, as well as academic recognition, since these projects will be submitted to the Westinghouse Foundation in the fall. Other Benefits of Program
An additional benefit of this program was the retaining of high school personnel during the summer months at the facility (to plan the next academic year's schedule). This provided benefits to this teacher's own knowledge base, the aca-
demic nroeram in the public schools, the program itself, and the comminity. The opportunity to spend the summer a t the site allowed this inst&tor to become acquainted with new instrumentation and recent developments. It gave this teacher the opnortunitv to observe the tvDes .. of skills required of a professional sientist. I t also gave this teacher the opport"nity to studv the interface between the chemist, chemical engineer, and product. This exposure is useful once the teacher is back in the classroom.~~ew topics such as liquid chromatography can he discussed. Science projects requiring better instrumentation are now in the realm of possibility. This teacher noticed that much of the time of a professional chemist or engineer is spent thinking and writing. These writing skills are very important in communicating one's ideas and research studies. Conseouentlv. - . more time will be allocated in the future on experiment write-ups and communication skills. Finally, the host facility gained its major objective of increasing its positive image in the surrounding community. The students involved became good-will ambassadors when they returned home. ~ m ~ l o ~ e ethe s& facility who came in contact or even saw the students as they came to the laboratory would report back to the community. Recommendations for Future Changes in Program Several weaknesses which need to be strengthened were noted. One is that a greater amount of time needs to he spent on assessing and providing guidance in reference to the science projects. To alleviate this problem, a greater amount of time will be scheduled for conceptualizing projects, determining what data is needed, and designing time completion schedules for each ~ h a s of e the ~roiect. . . A second area which requires strengthening was instrument instruction. Durine the course of the proaram, the staff was overextended trying to provide inst&ction for several different instruments a t a time. Once a general introduction to each instrument is given, it would heheneficial for students to work ar an individual pare in trying to understand the instrumentation. ~ o w e v e rthe i instruction manuals that come with the given instruments are written at a non-instructional level. and students do not have the time to coordinate the manual with the instrument. A remedy for this situation would be t o develop an educational package that will provide background and test a student's understanding a t various nhases in the ~ a c k a e e T . o further assist the student, these instruments could be videotaped and the package made available to students anytime they need reference to them during the course of the program. Finally, more instruments need to be made available to students. In the coming year, we will add instruction in the Spectrographic Analyzer, an instrument which provides emission spectra on the basic inorganic elements. A liquid chromatograph will be available for special study for second-vear students in the Droeram. A second gas chromatograp& which is much more b&c than the larger research instrument. will be utilized and comparisons can be made on meter will be avnilahle data obtained with each. A research for a wide variety of studies. 'Che differential scanning calorimeter will he-utilized to a greater extent for research projects. Relevant Regulations and Policies Programs such as this one come under the guidance of the Civil Service Reform Act of 1978, Public Law 95-454, regarding non-paid volunteer service. According to section 308-13 of this law.. eovernment aeencies can accent such vol" unteer service agreements between the government agency and nublic or orivate institutions so involved. Students are not considered government employees but are eligible to receive comnensation for auv sustained while per. iniuries . forming this service under the N'orkman's Compensarion Act or the Federal Tort Claims ~rovision. The government agency such as the Army, Navy, etc. may ~~
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have additional guidelines. For instance, this program falls under the N a w Community Services Program. The purpose of this program is '.to asair; responsible private, local, state, and Federal a~encieswhich have primary concern for the socia1 and economic problems of the nation." Any activity generated which uses Naval Facilities must not (1) interfere with any assigned military mission, (2) must follow equal opportunity practices with regard to selection of participants, (3) should provide educational programs that are unique and dependent on the use of these facilities and not simply dunlicate alreadv existing- -nroarams in the community, and (4) should incur no additional expense to the Navy. Other Exlstlng Programs The onlv other Dromam which exists in the Washinaton area that ihe autl;or&e aware of is the Summer science Research Participation Program for High-Ability Secondary School Students sponsored by American University. In this uroeram, students spend 8 weeks engaged in research activi. ; i e ~ ~ ~ o n s o rbye di,rkanizationssuchas the National Bureau of Standards, Gillette Research Insritute, Goddard Space Flight Center. etc. Srudents ioin a team of scientists alreadv at Gork on a given research iroject, or they commence work on a planned uroiect which has been delayed. Thev are required to write a paper to present at a seminar which is held a t the end of the summer. Only high-ability and highly motivated students are selected for this program as determined by school records and test scores. Advantages and Disadvantages of Program to Sponsoring Institution The advantages of the program for the sponsoring institution vary depending on the type of program involved. Under the Navy program as already discussed, public awareness of the installation is increased. Furthermore, the program produces better qualified applicants within the local community which the Navy recruits for personnel. It can alsoincrease the source of available applicants for highly technical positions if such positions are in demand. In the American University program, the self-satisfaction of giving guidanre tn a young adult is gained on the pan of the scientist working with them. In some cases, research projects that were delaved because of the lack of adequate personnel could be contihued. The rime liabilitv nresent for the host institution is that i t takes time and wiiing personnel to do the paperwork and to administer such a program. This drawback can he minimized if there are ~ i l l & ~ p e r s o n n eat l , the puh!ic institution requesting the service, who will assist in this task. The other disadvantage is that some mission might be undertaken by the governmental agency which would prohibit that agency from completing the program. This could result in poor public relations. Summarv In summary, it appears that the guidelines have been established for all governmental agencies with the Civil Service Reform Act which is effective January 11,1979. It also appears that the benefits to the institution outweigh the disadvantages. Add to this the benefits that the students gain, and the procam . - can definitely. .provide a service to the community as well as enhancing an agency's future programs. The cooperative program between the US. Navy and Charles County Public Schools described fills a need for student contact with professional scientists working on scientific developments. It also provides the opportunity to work with advanced instrumentation. Results indicate that students benefit in terms of realistic career aspirations, displaying better lah techniques, increased ahilitv to inrernret ernnhical data, and a willingness to work . . . in science research as a volunteer. In the next year, shortcomings of this program will be met with the development of instr"ctional p&kiges. Volume 57, Number 5, May 1980 1 371
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