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    "D" is for Dissolve

    This column is for you real little ones - those of you who have just begun school and are learning your letters. You will learn the letter "D, d" with the basic scientific concept of dissolving something. Get a clear plastic cup, water, a pencil, a paper towel, a twist-tie, and a kool-aid packet.

    Please note:  All chemicals and experiments can entail an element of risk, and no experiments should be performed without proper adult supervision.

    Carefully cut the paper towel into four equal squares. Place about one teaspoon of Kool-Aid in the center of a square. Fold it shut and close it with a twist tie. Tie the ends of the twist tie around the center of a pencil. The pencil acts as a support rod to dangle the kool-aid packet into the empty cup - just place the pencil down lengthwise on top of the cup's opening. Pour water into the cup until it just touches the bottom of the packet. Observe for a while, then add some more water.

    Write your name on a sheet of paper and a title: "D d Dissolve" to practice your "d's". Then draw pictures of four simple cups. On two of them, draw your pencils and packets as well as you can. Draw in water levels on all four cups. (Or your teacher or a parent can have these already drawn for you). Now draw what happens when (1) the packet barely touches the water (2) the packet is soaked in water (3) when crystals are sprinkled directly to the water (no packet), and (4) after some time has passed. Using the paper towel, a type of "schlieren" effect occurs, like when heat waves are seen over a hot surface. You can also try other materials to test whether or not they will dissolve, such as table salt (yes), sugar (yes), or sand (no).

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    Kathleen Carrado Gregar, PhD, Argonne National Labs 
    [email protected]
    December 1998

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    Thanks and acknowledgements to Marlisa Ebeling, a primary level teacher in Naperville District 203.