What You'll Need:
White cone-shaped coffee filters (Melitta-type)
Washable color markers
Scissors
Clear plastic cups
Water
Cut a coffee filter as shown in the pattern at right. When you
are done, open it up to make a butterfly shape. Color designs on the wings with markers. You don't have to cover the entire wing, and they don't have to be the same! Don't put colors on the "body" part on the bottom.Pour about 1/2 inch of water into a plastic cup. When you have finished your artistic creation, shape the filter back into a cone and place it in the cup. The "body" should just be in the water. Sit back for about 10-15 minutes and watch what happens. When the water has reached the top of the butterfly, take it out of the water and let dry.
First of all, you will see the water start to move up the coffee filter. This is called capillary action, and it's the same reason that paper towels can blot up spills. But as the water moves into the areas you colored, you'll see something strange happen. The colors don't stay where you put them! Some of them will move. Others will spread out into weird shapes. And still others will break up into more colors! The final butterfly pattern probably doesn't look anything like what you started with. Why does this happen? Because the inks in the markers are washable, they dissolve in water. So when the water reaches them, they can be carried along with it.
This is an example of a technique scientists call chromatography, which is Latin for "writing with color". Chromatography is used to separate complicated mixtures so that they can tell what's in them, even if the things being separated don't have color. Scientists have all kinds of interesting gadgets that let them "see" things that are invisible!
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