CREEPING, CRAWLING COLORS

Test the rainbow with two sweet experiments.

- by Rebecca E. Hirsch

A PIECE OF GREEN CANDY may look like a single color, but is it? Some inks and dyes are made of one color; others contain hidden colors. You can be a science detective and find out what really gives candy its color.

Chromatography is a way to separate out the different colored molecules in a mixture. You dab a substance, such as ink or dye, onto paper. Then you dip the paper into a liquid. As the liquid creeps up the paper, it picks up the colored molecules and carries them along. Different molecules crawl along at different speeds, based on how heavy they are and how well they dissolve in the liquid. The pattern of bands reveals what is in the mixture.

Rainbow Candy

What makes up the colors in your favorite candy?

Paper towel or coffee filter

Scissors

Pencil

Water

Plate

Colorful candies

Clock or timer

Salt

Measuring spoon

Measuring cup