Using Concept Maps as a Tool To Apply Chemistry Concepts to Laboratory Activities Mark Stensvold Division of Education, Indiana University at Kokomo, 2300 S. Washington St., Box 9003 KokomoJN 46904 John T. Wilson Science Education Center, University of lowa, lowa City, IA 52242 Laboratow-centered instruction continues to be an effective and necessary pan of chemistry education. However, students frcauently lack the insight or skill to atisociatc laboratory experience with appro$ate chemical concepts. They, therefore, are unable to make what is seen and done in the laboratory meaningful in terms of those chemical concepts. Teachers need to anticipate this problem and apply instructional techniques that help guide students to apply chemical concepts in laboratory activities. One such technique is concept mapping.
effective laboratory activity The laboratory environment contains considerable distracting information or "noise" that is extraneous to concepts of importance. Students must recognize and disregard this "noise" and identify important information in order to form appropriate associations with exolanatom concents (1):Further. if an exnerience in the laboratory IS new, students may have difficulty lookine oast the ohvsical asoects of the actlwtv to the concepts tobe learned &om theLactivity(2). Several methods have been used to help students prepare for laboratory activities (3). Students have written summaries of laboratory procedures and used those summaries to do the lab (4).Flowcharts have also been used to analvze laboratom ~rocedure(5). While these methods focus on understanding laboratory procedures, the problem of imposing conceptual structure on laboratory activi-
Limits to Laboratory-Centered Instruction Laboratory activities have some features which, if not anticipated, can cause students difficulties not typically seen in textbook-based instruction. While textbooks present content with an imposed conceptual structure, oRen the laboratory does not. Students can use t h e provided textAtoms book structure to associate specific facts within a n appropriate conceptual framework. For example, students gain greater meaning concerning the "parts of an atom" when they associate those parts with concepts about I "atomic structure". contam Or creates I n many laboratory 1 activities, students Neutrons Protons Electron: are left to find their own conceptual \ s t r u c t u r e s which even number of may or may not be meaningful or effective. neutral The lack of an imposed conceptual structure is not the only impediment to Figure 1. Portion of concept map made by student after laboratory activities.
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ties is not addressed. The present study was designed to investigate one method students can use to impose their own conceptual structure on laboratory activities. Concept maps have been seen as a means of encouraging students to integrate new concepts into their conceptual structure (6, 7).As students generate concept maps,-they cast and recast their own understanding of a set of related concepts . bv- preparing . . ., a diamam of those concepts. To construct a concept map students first dcveiop a list ofconcept words. The most eeneral concept . is .placed at the too of the map, and succes&ely less general concepts are piaced in lower positions. Two concepts of equal generahty would be placed next to one another on the same level. Fimre 1 is a portlon of one student's concept map. It represents that student's personal conceptualiz&ion bf chemical bonding. In the figure, the concept "atom" is more general than the concept "electrons". The concepts "neutrons" and "protons" are of equal generality. Eventually, the student builds a hierarchy of concepts with the most general at the top and the most specific at the bottom of the page. Concepts are connected to indicate their relationships. Lines and arrows are drawn to indicate these connections. Finally, words to express the type of relationship are added to the connecting lines. For example, "atoms" - '%aven"parts". Several researchers have reported enhanced achievement through the use of concept mapping. Bousquet observed a positive relationship for those students who mapped concepts well and performance on achievement tests (8).Novik, Gowin, and Johansen (9)described a study where seventh and eighth grade students learned to use and apply the tool in a six-month trial. Students who had been taught concept mapping made more "valid relationships" in a test using a problem-solving incident. Pankratius (10) found that high school physics students who concept mapped before, during, and after a threeweek physical science unit scored higher on an achievement test than those who m a ~ ~ onlv e d after the unit. Both of the mapping groups scorzsignifi&ntly higher than a control m o u ~which did not map. These studies sueeest a relationshipbetween concept mHpping and improved comprehension. The present studv was a n attempt to attain k r t h e r data on tl& relationship and to investiiate the use of concept mapping .. - in coniundion with chemistrv laboratories.
Non-Mapping Group
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Method A total of 180 high schwl students participated in this study, which was presented as an extension of an ongoing unit on chemical reactions. Classes were randomly assigned to either control or treatment groups. Both groups were found to be equivalent in terms of general ability as measured by the Iowa Tests of Educational Development (ITED) (11). Students in the treatment group constructed concept maps, before and after the laboratory activities, based on their own understanding of chemical bonding. (Chemical bonding was the conceptual basis of the laboratory activities thev completed.) It is importint to realize that student concept maps represent their own conceptions-how thev perceived the information given to t h e m h a text, lecture i n d laboratory No master concept map was taught to them. Students in the control group completed the same laboratow activities but did not construct concept maps. The laboratory activities were based on four chemical renctions as examples of chemical bonding. (11neutralizing an antacid magnesium oxide and hydrochloric acld,, (2, produc-
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[TED Vocabulary Subtest Figure 2. Regression slope lines-vocabulary predicting comprehension score. ing carbon dioxide using baking soda and vinegar and reacting the carbon dioxide with limewater, (3) making carbonic acid by bubbling carbon dioxide through water, and (4) producing oxygen using hydrogen peroxide and chicken liver and then burning splints in oxygen to produce carbon dioxide and water. Students were provided with written procedures and necessary equipment. They performed the procedures and wrote the reactions in symbolic form. After completing the four activities, both control and treatment mouns completed a comprehension test which assessed & t u h information and concepts from the laboratory, and concepts related to chemical bonding but not directly related to the laboratory ~
Results Unlike the studies cited above, no significant differences were found between those who constructed concept maps and those who did not when only group scores on ihe comprehension lest were compared. However, it is unlikely that any instructional technique, such a3 concept mapping, wuuld bc equally beneficial LO all students. In some cases, the lack of differences between groups can be attnbutrd to differential interact~onsof individual student abilities with the instructional technioue. Studcnts in one group fare better than similar students in the other group. Interactions between the instructional techniaue. concept mapping, and student ability were anticipated in this study. Some students were expected to learn more about chemical bonding with the support of concept mapping while other students learned more without such support. Interactions of this type are identified as aptitude x treatment interactions (AT11 and were first described by Chmnbach and Snow (12). In this study, AT1 were evaluated by comparing student verbal ability, as measured by the vocabulary subtest of the Iowa Test of Educational Development (131, to their comprehension test score. Treatment and control group regression slopes were compared using a n analysis of covariance and found to be significantly different (p < 0.05); Figure 2 illustrates this differential relationship. For students with high verbal abilities, those who constructed concept maps scored more poorly than those who did not construct maps. While for students with low verbal
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ability, those who constructed concept maps scored higher on the comnrehension test than those who did not construct mapi. This result is not unlike other AT1 research where a treatment can limit or interfere with students' customary approach to learning and comprehension (14). These results are once again a reminder that students have different abilities and instruction interacts differentiallv with each student. In this study. -. only - low verbal ability students gained from the concept mapping experience. If concept mapping in another manner, high verbal students may also find the technique facilitative. Discussion This study grew out of the general concern that students not only be able to perform chemical laboratory activities accurately, but also be able to explain their findings using relevant chemical concepts in an appropriate, meaningful way. This concern reflects a general tenet concerning knowledge, that i t is more than a remembered list of fads. Concept mapping appears to facilitate, a t least for some students, this type of learning during laboratory instruction. "Low ability students" in this study included those whose score was lower than 14 on the ITED vocabularv subtest. In a typical high school chemistry class, about haif of the students should be ex~ectedto have l o w verbal ability" scores.' These studengbenefit from concept mapping in these ways: 1. In generating a concept map, students practice using specific concept labels; 2. The structure provided by a concept map may enable students ta attend selectivelyto important informationand ignore distracting features of laboratory activity; and, 3. Constructing a cancept map a h r a laboratory activity should encourage students to integrate the information ac-
'It was estimated bv R. Forsvth of Iowa Tests of EducationalDeveC opmentthat 57%of n h h gradistudentsnationally would score below 14 on the ITED vocabulary subtest. 2A thorough discussion of teaching concept mapping may be found in reference 9.
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quired from the laboratory experience with chemical concepts in a meaningful way. When using concept maps, it is possible that students with high verbal abilities limit their perceptions in the lahoratory. They may select and attend to too little information in the laboratory. Furthermore, concept mapping may be more effective if students are encouraged to revise their concept maps periodically during the liboratory activity. Providing for student's conceptions to change as conflicting evidenceis ~erceivedis in the snirit of shentific inouiG " and well suited to the chemistry iaboratory. A
Conclusion Laboratow instruction can become more effective when instructionh techniques are incorporated that help improve student comprehension of related concepts. These techniques should (1) reduce attention to distractions within activities, (2) im~roveunderstanding of directions and procedures used i n a laboratory, (3) ticresults to ap~ r o ~ r i awt en c e ~ t known s before or resented with the aciivity, and (4)&prove the integration of laboratory content with a n individual's conceptual structure. Concept mapping is one technique that teachers can include easily as part of laboratory instruction.' Literature Clted 1. Johnstam, A. H.' Cham. Edve
1984,61,847.
2. Beasley, W S c i e m Edue. 1986. 63,567. 3. Wilaon, J.T.; Chalm-Neubsuer, I.C. J Chrm. Edue 1988,65,996. 4. PickeMg, M. J. Chem. Educ 1987,64,521.
5. Mullin, W J.: Tidswell, J, unpublished resub. 6. Nousk, J. D.: Cawin, D. B. kornzng Holu to h m ; CambridW Univemity Reas: NewYor*, 1984. 7. Ausubel, D. P.; Novak, J. D.; Hanesias H.Edvmliond Psychdolgv: A cog nil.^ Vmw, 2nded.: Holt, Rimhart, & Winrton:NewYork, 1978. 8. Bausquet, W. S. PhDThesi., Ohio State University, 1982. 9. Novak, J. D.; &%urn, D. B.;Johanaen, G.T Sclonce Edvc 1988.67.625. 10. Panltratius, W . J , unpublkhed result.. . 11. Feldt, L S.: Fmyth, R. A,: Alnof S. D. manual for Teachers. Adminiabatma, and Counaelom-Iowa Test.afEducationd Development' IowaTestingRograms: Iowa City, 1987. 12. Cmnbach,L. J.;Snow,R.E.AnifdesondInahlctio~IMethals:IrvingtonPubBahera: New Ymk, 1971. 13. Ref. 11. 14. K0ran.M. L.;Koran, J. J. Jr. J.ReswrchSciomIPoehing, 1880.17.417.
