This fun fall science experiment that teaches children how to see the rainbow in a leaf. An easy project that only requires simple household materials, this leaf chromatography experiment reinforces why leaves turn different colors in the fall and other fascinating photosynthesis facts found in LIFEPAC® and Switched-On Schoolhouse® sixth grade science lessons from Alpha Omega Publications®. Plus, your child will also gain a deeper understanding of God's marvelous design of a leaf.
Materials:
Assortment of green leaves
Small jars (baby food jars work great)
Jar covers, aluminum foil, or plastic wrapRubbing alcohol
White paper coffee filters
Shallow pan
Hot tap water
Tape
Pens
Plastic knife or spoon
Kitchen timer
Scissors
Notebook
Procedure:1. Gather two or three large leaves from several different species of trees. (Maple trees and other trees that have dramatic fall color changes work best). In a notebook, designate a page for each of the leaves and record the different colors you see in each of the leaves.
2. Cut two long, thin strips of coffee filter paper for each jar. Use half of the coffee filter strips to label the jars with each tree's name and location.
3. Tear or cut the leaves into tiny pieces and put them into separate small jars.
4. Add just enough rubbing alcohol to cover the leaves in each jar. Carefully chop or grind them into the alcohol using a plastic knife or spoon. NOTE: Isopropyl rubbing alcohol can be harmful if not used correctly. Read label warnings and directions carefully.
5. Loosely cover the top of the jars with lids, plastic wrap, or aluminum foil.
6. Place the jars into a shallow pan filled with one inch of very hot tap water.
7. Allow the jars to stand in the hot water for at least a half hour (longer if necessary) until the alcohol has become colored (the darker the solution, the better). Gently swirl each jar every five minutes and replace the hot water if it starts to cool.
8. Uncover the jars and remove them from the water.
9. On one end only, label the remaining coffee filter strips with each tree's name and location.
Then, place the strips into the appropriate jars, so one end is immersed in the alcohol, and the labeled end is wrapped around a pen suspended across the top of the jar. Secure the piece of paper with tape.
What you'll observe: The alcohol will slowly begin to travel up the paper, bringing the colors in the leaves with it. After an hour or two, the colors will travel different distances up the paper as the alcohol evaporates.
Depending on the type of tree, your homeschooler should see different pigment shades of green (chlorophylls), yellow (xanthophylls), orange (carotenoids), and red (anthocyanins) from the leaves.
10. Remove the strips of pigmented paper before the alcohol reaches the top and allow them to dry. The finished paper strips are called chromatographs. Tape them to the pages of your notebook and record your observations. How many colors are visible? Could you see the same colors in the leaves before the experiment? Based on your fun fall experiment, which tree leaves do you think will turn the brightest and least bright this fall?
