Save the Planet!

Name: Period:

The ozone hole is too big, and too much dangerous ultraviolet radiation is getting through. You need to find the best chemical for blocking ultraviolet radiation.

Materials:

*Ultraviolet beads – They change color when ultraviolet light hits them. The stronger the color change, the more ultraviolet light is hitting them.

*4 different chemicals that could block ultraviolet radiation.

*Plastic bags – Used to hold the beads when testing the chemicals.

1) Get into groups of 4. Get five beads that have the same color. See what happens when you put them in sunlight outside.

2) Spread one of the chemicals on a plastic bag (don't spread too thick!) and put a bead in the bag. See if it looks different than a bead outside of the bag. Remember that the chemicals have to be spread on the plastic bag so that they're between the bead and the sunlight.

3) Now try testing the other chemicals. On the back of this handout, write what you observe for each chemical. (Example: Chemical 1: The bead changed color a little bit – it became light blue).

4) Use these observations to figure out which chemical blocks the most ultraviolet radiation. Remember that if a bead has a strong color change, more ultraviolet radiation is getting through.

Questions:

1) Which chemical blocked the most ultraviolet radiation?

2) How did you know?