Student-made periodic table - Journal of Chemical Education (ACS

Betsy St. John, and Gordon Stevens. J. Chem. ... periodic table is used for class reference throughout the school year. ... High School / Introductory...
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Student-Made Periodic Table Betsy St. John and Gordon Stevens San Rafael High School, San Rafael, CA 94902 High school chemistry teachers frequently encounter the problem of having to create imaginative homework assignments that are fun for high school youngsters yet zero in on expanding their working knowledge of chemistry. We think we have come up with an assignment that boosts student self-esteem by displaying their creative artwork and awakens interest in the high school library-an often neglected source of chemical information. Having high school students write formal reports on chemical elements can be educationally deadly. In a typical high school classroom the range of abilities is so great that marking the assignments in a meaningful way is nearly impossible. We have devised a variation on this assignment that has transformed student enthusiasm 100%. In the assignment each student picks a numbered slip of paper out of a large beaker that becomes the number of hisher assigned chemical element. Each student is to write a report on his1 her selected chemical element on one side of an El/%-X 11-in. piece of paper. The student reports are posted on a large array of sheets of insulation board marked with the outline of a standard periodic table. This very large, student-made periodic table is used for class reference throughout the school year. School libraries have adequate information in various encyclopedias and technical references. The assignment also serves as an excellent introduction to the CRC Rubber Handbook of Chemistry and Physics, which many high schools have in each chemistry room. Students will need some guidance in the formats of their reports. The symbol, atomic number, and molar mass will have to be sufficiently large and uniformly placed to be easily seen from afar. The teacher may want a list of physical properties in column form: melting point, boiling point, density, ionization energy, etc. Key chemical properties, the element's discoverer, and its chief uses are some of the many things that can be

included as part of the report. We encouraged student creativitv to include the use of graohics and color. MAYof the reports we received were spectacular, and we had nearly a 100% turn-in rate. We found many of the students would spontaneously gather around and read the reports of others to themselves. They were amazed how much interesting information was accessible by perusing these reports. Construction Plan Materiels 5 sheets of 4- X 8-ft insulation board 42 ft 2- x 4-in. construction-grade fir 28 l/q. X 3112-in.lag screws and washers

%in. black felt pen Since the standard neriodic table has 18 columns and seven raws and each location has'to accommodate an a12- X I I -in. report, four 4 - X 8-ft sheets juxtapositioned in a parallel manner works nicely if the element locations are 10 X 12 in. in size leaving room for 6-in. borders at the top, bottom, right, and left of the entire table. M'e found it easiest to lay the sheets down on the claxsrtrom floor, pencil in the lines of the periodic table with a straight edge, and then go over the penciled lines with a ' - i n . felt-tin nm. To do the actinide and lanihanide series, another sheet of insulation board is cut lengthwise on a table saw ta make a piece 32 in. X 8 ft. The remain-

Figure 2. Cross sectlon of mounting rail.

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Flgure 1. Layout of ludaposltioned sheets insulation board surrounded mounting rail. Doned lines are edges of insulation board. IS4

Journal of Chemlcal Education

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Figure 3. Student-made periodic table.

ing 16-in. X 8-ft piece is cut into three equal 32- X S i n . pieces and again juxtapositioned to makes 32-in. X 12-ft array with no scrap (!). The 10- X 12-in. element locations for the 14-column,two-row actinide and lanthanide series are penciled in and marked as before with 4-in. border at the top and bottom and 2-in. borders at the left and right. The title, periodic table, was printed in large letters in the appropriate place. The layout of the sheets of insulation hoard are shown in Figure 1.

Since the assemhled table is impressively large, some care has to he taken in mounting. Not finding amounting rail that was commercially within our means, we opted to fabricate our own from construction-grade fir using the wood shop's tahle saw. A cross section of the mounting rail is shown in Figure 2. The assembled, studentmade periodic fable is shown in ~ i g u r e3. The cost of the project was just under $80. The materials are available at local building supplies.

Volume 66

Number 2

February 1969

155