Kids, have you ever seen an arrangement of small white boxes containing a collection of one- or two-letter symbols and bunches of small numbers? Chances are that, if you have, it was something that chemists use called the periodic table. You might even have one in your house if someone you live with has a chemistry or physics textbook, a scientific encylopedia, or access to the internet (try www.chem4kids.com and click on "elements"). Nature and science discovery stores sell placemats of it, too. Look one up and try to figure out what the symbols stand for.
The table has information about every element found on Earth. After many years of studying chemical elements, scientists have discovered or created over 100 different elements. Every gas, liquid, solid, rock, metal, compound, and mixture in the universe is made up of some combination of these basic elements. In the typical periodic table, elements with common properties fall in the same column. The overall arrangement makes sense to chemists but it is highly technical and not very approachable for the young or non-scientist. Everyone can have fun with it, however, when a different and more light-hearted approach is taken.
One such presentation distorts the shape of the boxes of each element to reflect its relative abundance on Earth. This way the largest boxes contain the most commonly known elements, such as those for C (carbon), O (oxygen), and Si (silicon). Check this out in the Journal of Chemical Education, volume 70, page 658, August 1993. A sample chart with a full activity's description for elementary school students and teachers is provided.
In addition to this, some colorful charts for display can be ordered from various places, such as Aldrich Chemical Co. (800-558-9160), Gelest Inc. (215-546-1015), La Naturaliste in Canada (418-724-6622), and Time-Life Books published a giant poster in 1987. A company called "Food for Thought" will provide posters for "eaters and thinkers" of food items, vegetables, desserts or even animals in take-offs of the original (800-666- 5436). Have your parents or teachers check into these for you!
Please note: All chemicals and experiments can entail an element of risk, and no experiments should be performed without proper adult supervision.
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Kathleen Carrado Gregar, PhD, Argonne National Labs
[email protected]
June 1998
