Science Fair Project for 8th Grade

In fall, we observe that trees change their colors. In this science fair experiment for 8th grade we will determine the reasons why leaves change their colors in the fall. Maybe they stop making food so the green chlorophyll disappears from the leaves. As the bright green fades away, we begin to see yellow and orange colors. Small amounts of these colors have been in the leaves all along. This may be the reason leaves change color in the fall.

Hypothesis

Since leaves do not have the materials they need to survive in the winter and fall, their leaves die and loose the green color.

Materials

1. leaves, small jars
2. rubbing alcohol, paper coffee filters
3. covers for jars or aluminum foil or plastic wrap
4. shallow pan, hot tap water, tape, pen
5. plastic knife or spoon, clock or timer.

Procedure

1. Collect 2-3 large leaves all from different trees.
2. Cut the leaves into very small pieces and put them into small jars labeled with the name or location of the tree.
3. Add enough rubbing alcohol to each jar to cover the leaves.
4. Using a plastic knife or spoon, carefully chop and grind the leaves in the alcohol.
5. Cover the jars very loosely with lids or plastic wrap or aluminum foil.
6. Place the jars carefully into a shallow tray containing 1 inch of hot tap water.
7. Keep the jars in the water for at least a half-hour, longer if needed, until the alcohol has become colored, the darker the better.
8. Twirl each jar gently about every five minutes.
9. Replace the hot water if it cools off.
10. Cut a long thin strip of coffee filter paper for each of the jars and label it.
11. Remove jars from water and uncover.
12. Place a strip of filter paper into each jar so that one end is in the alcohol.
13. Bend the other end over the top of the jar and secure it with tape.
14. The alcohol will travel up the paper, bringing the colors with it.
15. After 90 minutes, 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, orange or red, depending on the type of leaf.
16. Remove the strips of paper.
17. Let them dry.
18. Tape them to a piece of plain paper.

Results and Analysis of Data

By separating the colors of a green leaf using chromatography, list down all your observations.

Conclusion

With the interpretation of results and analysis of date, you can come up with your own conclusion.