Do you know where the beautiful colors of fall leaves come from? They are there in leaves all along, they’re just being masked by the green chlorophyll each leaf uses to make food during the warm, sunny months. I wanted to show my students how this process works therefore, I came up with a simple autumn colors leaf experiment! Using chromatography, my students love to separate the pigment molecules in fresh leaves, revealing some of the leaves “hidden” colors. Each year when I complete this activity with my students, they are always amazed at how the leaves change colors. This experiment will surely be a hit in the classroom plus, you can pick up all of your supplies at your local Dollar Tree for just $1 each.
Gather Your Supplies:
- Several Leaves from Different Trees
- Small Glass Containers
- Rubbing Alcohol
- Paper Coffee Filters
- Shallow Aluminum Pans
- Hot Tap Water
- Aluminum Foil
- Sticky Notes
- Plastic Spoons
- Tear, cut, or chop the leaves into really small pieces and put them into the glass containers. Using a sticky note, label each container with the name of the tree.
- Add rubbing alcohol to each container, enough to cover the leaves. Use the plastic spoon to grind the leaves into the alcohol.
- Loosely cover the containers with aluminum foil and place them in your shallow pan filled with about one to two inches of hot tap water.
- Keep the containers in the water for about a half-hour (or more, if needed) until the alcohol has become colored (the darker, the better). During this time, you should gently shake each container every 5 minutes and replace the water in the pan if it cools down.
- Using the scissors, cut a long, thin strip of coffee filter for each container and label it with the tree name.
- Remove the containers from the water and remove the aluminum foil covers. Place the coffee filter strips into their respective containers allowing one end to be immersed in the alcohol. Bend the other end over the top of the container and tape it down.
- The alcohol will travel up the paper, bringing the leaf’s colors with it. After 30-90 minutes (maybe longer), the colors will travel different distances up the paper as the alcohol evaporates. You should be able to see different shades of green, and possibly some yellow and orange.
Science Facts: Where do the beautiful colors of fall leaves come from? They are there in leaves all along, they’re just being masked by the green chlorophyll each leaf uses to make food during the warm, sunny months. As days get shorter and colder, trees shut down the food-making leaves for the winter and stop making chlorophyll, which means the green goes away. Once this happens, the other color pigments in the leaf begin to show through, and the leaves change colors. Using chromatography, your students can separate the pigment molecules in fresh leaves, revealing some of the leaves “hidden” colors.
Looking for more activities for the classroom? Check out these 3 Clever Indoor Activities for Students!