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Tuesday, October 13, 2015

Maple Leaf Science: how to extract chlorophyll and paint a duck

science for little kids, chlorophyll extraction, maple leaf art, why fall leaves change colors

Something interesting happens when you add maple leaves to alcohol.  Do you want to hear what?  I should probably start in the beginning.

One day I was sitting in a backyard watching my 2-year old wash maple leaves. 

After the leaves are thoroughly washed, they are usually dried with towels.  The whole activity (if I am lucky) lasts long enough for me to read a couple of pages in a book without pictures. 

This particular day I didn’t have a book to read.  I stared at the sky.  I looked at the clean leaves and started wondering what else can we do with clean maple leaves. 

Sitting is not my natural state of being so I got up, took some of the dried leaves in a house and put them in a blender.  I once read that the moisture content of fall leaves is 85-95%, so it came as a surprise that virtually no moisture came out of the leaves.  Actually, the leaves felt pretty dry to the touch.   I don’t know what normal people would have done at this point, but I dumped the crushed maple leaves in a large pot, added some water and boiled them for 10 min, 30 minutes, 60 minutes.  

I was just curious if the water will turn green and if yes, would the color be intense enough to use as a green paint. 

The water did turn green, but the color was pretty light.  The lightness of the color didn’t stop my son from wanting to paint with it. 

From four-years of school chemistry classes I vaguely remembered that the mildly alkaline quality of baking soda sometimes helps to bring out colors (i.e. it does a good job of bringing out blue color out of red cabbage).   However, playing with baking soda didn’t do much to improve the intensity of color in our maple leave mixture. 

So the next natural step seemed to be alcohol.   My grandma, who was a chemist, used alcohol on everything, from bugs to kids and everything in between.  (I’m sure you don’t want to try her cold remedy on your child.  You do?  Ok, add crushed garlic to a drop of food grade industrial alcohol and make a child drink it.  Oh so you changed your mind?  I thought so).  Alcohol turned out to be the best thing to extract the color from maple leaves!  In case you want to try this experiment at home I will now outline the steps for you.

How to Extract Chlorophyll 
from Maple Leaves

What you will need
  • Fresh Maple leaves (we washed them, but feel free to skip this step)
  • Alcohol (we used the regular Isopropyl alcohol 91% sold at Walgreens as first aid antiseptic)
  • Food processor or Blender (we used food processor equipped with a S-blade. I once blew up our smoothie blender doing one of my science experiments, so now I’m very cautious about using that kind for projects)
  • Pot with water
  • Mason Jar
  • Cheesecloth

 1. Remove stems from maple leaves.  (My kids LOVE this step. You can use the stems to practice alphabet).

2. Add maple leaves to the blender and process until all leaves are the same consistency.  (NOTE: You can add whole leaves to the alcohol to achieve the same result, but you will need bigger pot and more alcohol).  

3.  Fill a pot with a few inches of water and place over medium heat.  Place mason jar with alcohol in the pot.  Note: In our experiment: we used 2 Tablespoons of alcohol for each ½ cup of mashed leaves.  Make sure your leaves are entirely covered.  

4. Once alcohol warms up (NOTE: alcohol is highly flammable, you only need to get it warm and no more), add leaves to the mason jar and wait 15min, 30 min, 60 min.  Check on the color as you are waiting.  This is the exciting part!  You can see the alcohol turning dark green color!  It’s the pigment from the leaves moving into alcohol.

5. Now you can put small portion of leaves onto a cheesecloth and squeeze the liquid out. 

My kids were absolutely amazed! And so was I!

Look how strong the color is!  We used a dropper to transfer some chlorophyll to a wine glass just for the sheer pleasure of watching it swirl and twirl on the way down.

art and science of maple leaves

  Another thing we will try next time is acetone.  I didn’t have any in a house for the a long time because I stopped using it for removing nail polish but I remember doing many exciting experiments with it. 

Start by looking at green maple leaves with your kids.  Magnifying glass makes it even more fun.  Ask, Why are leaves green?  This is a great answer/guess!  I like how your mind works.  Have you heard of the word “chlorophyll”?  The green color in a leave comes from chlorophyll [klor-uh-fill].  Chlorophyll absorbs sunlight and helps plants manufacture their own food by the process called photosynthesis

Do you know why maple leaves turn yellow and red in a fall?  Interesting answer!  Along with chlorophyll leaves contain yellow and orange cartenoids.  Those additional colors are masked by the greater amount of green coloring.   As autumn days gets shorter and colder, maple leaves stop producing chlorophyll.  Once the chlorophyll is gone, green color disappears and other colors become visible.  That's why maple leaves become red, yellow and orange in a fall! 

I. Painting with chlorophyll

This is a finger painting.  This picture was painted by dipping index finger into the extracted chlorophyll.  Doesn’t the color look great?  Conventional finger paint move over!  What’s more chlorophyll paint didn’t fade over time. 

II.  Creating with pulp
And what about the pulp inside the cheesecloth?  We couldn’t just toss it away!  Oh, no!    

I drew a maple leaf on a piece of paper.  We covered it with A LOT of glue and then stuck the pulp to it.  Voila, 3D maple leaf.  Sprinkle it with green glitter generously and look at it lovingly any time you feel like you don’t do enough projects with kids. 

Extension activity
If green plants are green because they contain chlorophyll, does it mean that adding chlorophyll to some plants will make them green or greener?   I had to find out!  I picked white flowers from the backyard and put them into a wine glass filled with water and extracted chlorophyll. 

What do you think happened?  Do you think white flowers turned green?  I will leave you in suspense for today as this is a subject of another post. 

Do you like maple leaves?  What are your favorite leaf projects?  

Related Post:
 Plant Science: chlorophyll as a coloring agent