Why Leaves Change Colour Science Experiment

By October 18, 2017Parkland Players

Today we are taking a break from our literacy series. We have been having some overdue fall weather here in the Lower Mainland lately. A wind storm came in yesterday and blew a lot of leaves off of trees in the area, and so we wanted to share this fun fall science experiment to take advantage of the current weather conditions. So here it is.

WHY LEAVES CHANGE COLOUR SCIENCE EXPERIMENT

 

Materials

  1. 3 leaves (from the same tree)
  2. Rubbing alcohol
  3. Jar
  4. Plastic baggie (or plastic wrap)
  5. Paper coffee filter
  6. Small bowl or pan

Instructions

  1. Background information: This is good to know for your own understanding and discussion with children Leaves contain a chemical structure called chlorophyll. Chlorophyll makes the leaves green and it is strong enough to cover other colours in the leaves. This science experiment lets us separate the colours. Do not tell children this before hand, let them do the experiment and hypothesize on their own what will happen and why.
  2. Have children break the leaves into small pieces and place them in the jar.
  3. Pour rubbing alcohol over the leaves so that they are covered.
  4. Mash and stir the leaf/rubbing alcohol mixture until the rubbing alcohol turns green. Be sure to do this very thoroughly.
  5. Cover the jar with plastic and place it in a small bowl. Pour hot water into the bowl. Leave it like this for 30 minutes minimum (45 to an hour is better), swishing the jar around occasionally to stir the leaves. By the time it is done the alcohol should be a very dark green.
  6. Cut a strip in your paper coffee filter so that it can reach the rubbing alcohol but also hang over the top edge of the jar, tape it to the end of the jar if you need to).
  7. The liquid will travel up the coffee filter along with the separated colours. If you soak it for about 30 minutes you will get the best effect. The coffee filter should turn varying tones of yellow and green to show the colours that are hidden under that green chlorophyll.
  8. Discuss how you think the experiment worked with the children. What did the exercise represent about the properties of leaves?

Image Source: https://www.thesca.org/connect/blog/why-leaves-change-color-fall

Activity Source: http://www.howweelearn.com/science-experiments-for-kids/