edited bv
chemistry for kids
LINDAWOODWARD The University of Southwestern Louisiana Latayene. LA 70504
Presenting the Fun Side of the Periodic Table Kathleen A. Carrado Chemistry Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, IL 60439 "What do you do for a living?", they ask. The response "I am a chemist" usually results in a blank stare from the elementary school-age student. While this can be frustrating, it is understandable because of the technical nature of our field and the remoteness of direct contact between a child of this age with a professional scientist. The following guide was developed to help demonstrate the relevance of chemistry-and of chemiststo the everyday lives of these students, and has been used successfully with fourth and fifth graders. With slight modifications in presentation, it also can be appropriate for students in grades 3-6. This is designed to be a handson and interactive approach to showing students that they, without realizing it, already have learned some chemistry
It is hoped that they also can appreciate how common and non-threatening the world of chemistry can be. Adapting a Periodic Table Many elementary education teachers are familiar, but not comfortable, with the rather formidable presentation of the chemical elements-the periodic table. Amore attractive chart has been adapted from one originally constructed by W. F. Sheehan (I)(published in a similar form by the company Instruments for Research and Industry in their 1978 calendar). As displayed in the figure, each element is depicted by its relative abundance on the earth's surface, so that larger "boxes" are given to the more abundant elements. For instance, oxygen is the most plentiful a t a certain percentage that includes its presence both in
O 1970 Wm. F. Sheehan, as appearing in I'R Calendar for Scientists. All rights reserved.
The elements according to relative abundance. This is an example of how a fifth-grader might shade the chart during the described lesson. A blank chart and descriptive list of the elements can be obtained by writing to the author (K. A. Carrado at Argonne National Lab).
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Journal of Chemical Education
the atmosphere and in the earth's crust as a significant portion of rocks and minerals. Precisely because some elements are so common, most young students already will be familiar with the names and recognize their uses or compounds. [Because some elements exist in only minute quantities, especially the ones that do not occur naturally, some distortions of relative abundance in the chart were necessary.] With a colored pencil or crayon, the students are asked to shade the boxes of the elements as they are discussed in class, but only if they had heard of the element prior to the day's lesson. As the presenter systematically goes through the rows from left to right, the students are asked to guess a t the element's com~letename. and then to give examples of real-life uses and occurrences. At the pres&ters' discretion, if the students even recomize the uses for an element they can be allowed to shad; the box (for instance, diamond and graphite for carbon; gunpowder and matches for sulfur). Because the elements are weighted in size, usually about 213 of the table is shaded when the lesson is completed. The students are then asked to take a good look at how many of the elements they actually are aware of, and, therefore, how much "chemistry" they already know. They also very likely learned even more throughout the lesson. Indeed, the intense participation of most students makes this a worthwhile and rewarding experience for the presenter. Recognizing International Symbols Having actual specimens of some of the elements handy can h e l to ~ make the lesson more relevant and interestine. ~ x a m ~ iof e uses s should be provided when the students cfo not know an answer. It must be pointed out that while some of the symbols make sense, like A1 for aluminum, quite a few do not. Perplexed expressions occur when one proclaims that Na is sodium, for example. It should be stated that because this chart is used by chemists around the world, the symbols are international and no single language applies. Many symbols are derived from Latin definitions; for example, the derivation for sodium is natrium, and that for Pb, lead, is plumbum. Enhancing the Element Chart The lesson can be made more involved for the secondary grades 4-6. For example, the elements that occur as gases may have circles drawn to indicate bubbles, and the liquids are drawn in with wavy lines. The figure shows an example of how a fifth-grade student may complete his or her chart in this manner. Along the way i t probably will be necessary to point out that this chart contains all the known elements in the universe, and if a substance is not there, it means that i t is instead a compound -a mixture of two or more of the elements. Incorrect guesses have included air for AT,asphalt for As, and petroleum for P. An elementary discussion of atoms, molecules, and compounds can follow, so they may see that water, H20, is two hydrogen atoms and one oxygen atom combined to form a "molecule". Aforma1 periodic tahle also should be provided to each student, from which they can afterwards read the wrrect spelling of the elements. Creative Viewing of the Periodic Table There are numerous other creative ways in which the elements of this table may be discussed, limited only by the
imagination of the presenter. For instance, explore the common elements in a number of different compounds, or which ones are poisonous, or which ones are biochemically important. The resultingcolorful tables could be posted for open-house displays. An exercise called "An Element for a Day" fits in well here, where each student writes a short report about a certain element as if he or she actually were one, like iron, for example; "I am iron, a metal that is magnetic and . . .".The ''What's the Use?" column in this Journal provides excellent information about each element that can be useful for these exercises. lntroduclng the World of Chemistry This is designed to be a short, fun, and uncomplicated introduction to the chemical world for students anywhere from erades 3-6. deoendine uoon how involved the tooic is discussed. I have hiought ;hi; chart to several schoois for tutorials and have also incorporated it into part of a workshop for elementary education teachers. The response by both students and teachers alwavs has been enthusiastic. When presented as a workshop tb teachers, a tahle is provided that lists exam~lcsfor each element. alone with: ( 1 1 the pronunciation (2jthe state-solid, liquid or and (3) whether it is radioactive. This is quite important, because the average elementary teacher cannot easily come by this information. With the chart in hand and armed with the table of examples, an elementary education teacher can feel prepared to make this lesson eminently worthwhile. Both of these items are available by writing to the author. Teacher preparation is minor, and no supplies beyond those commonly found in a classroom are needed. Elementary education teachers usually have had minimal science education. althoueh several Dromams are underwav toward thei; continLng educaion-in the sciences (2,.?his article can be a useful tutorial for elementarv school teachers as a n introduction to chemistry. Maintaining - a Curiosity for Chemistry After graduating on to middle and high school, most elementan-aec students lose their inherent fascination with science. &t, perchance, a point will occur during a student's later schooling when his or her memory will be tickled by what was learned so many years eariier. It is hoped that intimidation by the "boring" or '?lard" classes like chemistry and physics will be somewhat alleviated. Perhaps the most immediate benefit is the demonstration of how "real" chemistry is, and that it relates in nonthreatening ways to everyone's daily lives. Acknowledgment The cooperation and helpful comments from W.F. Sheehan of Santa Clara University are greatly appreciated; Nellie Peters of 12R also was very responsive and supportive. Lynda Soderholm of ANL is acknowledged for beneficial hints in presentation, as are the reviewers of this manuscript. This work was performed under the auspices of the Office of Basic Energy Sciences, Division of Chemical Sciences, U. S. Department of Energy, under contract number W-31-109-ENG-38. Literature Cited 1. Sheehan, W.F. Chemistry 1978,49,11. 2. Duerst, M.A.J. C b m . Edue. lssO,67,1031
Volume 70 Number 8 August 1993
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