October 30, 2013

Lemon Science Experiments

Lemons are an incredible tool to use to teach science to children from preschool to middle school.  In the past, Sour Scientist was my favorite class to teach every week.  It was a class for middle schoolers when I was an environmental educator long ago.  Since then, I have adapted it for an elementary summer science camp.  Most recently, I spent some time in my son's class exploring with them a series of lemon science experiments for preschoolers.  These science experiments can be done individually or as a group.


Lemon juice and baking soda science experiments are perfect for preschoolers to first learn about chemical reactions.  Older children can complete the same experiments independently and investigate the science in detail.

(Sorry for the lack of pictures.  I do not have permission from the children's parents to share their faces.)


LEMONS {5 minutes}
Materials: Lemon, Letters L-E-M-O-N cut from yellow paper
  1. Give clues to children to guess what you want to discuss.  (Fruit. Yellow. Sour.)
  2. Explore what the children know about lemons.
  3. Spell LEMON with the children's help. 
  4. Examine a lemon.  
  5. Cut the lemon in half.  Provide each child with a small piece of lemon to examine.  
  6. Explain that, like an orange, you only eat the inside.  
  7. Have children taste the lemon.
Pennies {5 minutes}
Materials: bowl, pennies, lemon juice, paper towels 
  1. Children each choose a penny to examine.
  2. Each child examines their penny. 
  3. What do they look like?  (Brown.  Dirty.  Dull/not shiny)
  4. How much is a penny worth?
  5. Have each child place their pennies in the bowl of lemon juice. 
  6. The oxygen in the air reacts with the copper in the penny.  It makes the penny appear darker and not shiny.  It is called copper oxide.  
Complete the other experiments (except the fizzy lemonade) and then return to the pennies in the bowl.
     7. Want to see it?
     8. Rub the pennies with a paper towel.  The copper oxide shows brown on the paper towels.  Even without rubbing the pennies, the lemon juice was already working to clean the pennies. 
     9. Compare some of the other unclean pennies with the ones that were cleaned in the lemon juice.

Please Note: Though the copper content in pennies has changed over time, since 1982 all US pennies have a  copper plating (outside) and a zinc core.  A penny does not need to be pure copper to react with oxygen.  So you can just about any penny for science experiments!
The pennies on the left were as dark as the penny on the right prior to cleaning with lemon juice.
Mini-volcanos {10 minutes}
Materials: large tray or plate, lemon juice, 5 milliliter oral syringes, baking soda, spoon, small cup
  1. Place a spoonful of baking soda on a tray and lemon juice in a cup .
  2. Have each child use a syringe to draw up a little lemon juice to place on baking soda to erupt the "volcano" again and again.
  3. The baking soda is a base and it reacts with the acid in lemon juice to create carbon dioxide gas/air which is the fizzing bubbles.  Baking soda+lemon juice=carbon dioxide bubbles!
Blow up a Balloon {5 minutes}
Materials: water bottle (no label), lemon juice, baking soda, balloon, spoon, toilet paper
  1. Let’s blow up this balloon!  How can I do it?
  2. Is there a way to do it with lemon juice and the bottle? 
  3. What did we learn happens when combine baking soda and lemon juice?  We get bubbles!!  Could the bubbles help to blow the balloon?
  4. Place some lemon juice in the water bottle.  Add some baking soda to a piece of toilet paper and place it in the mouth of the bottle.  Place the balloon on top tightly around the mouth of the bottle.  SHAKE!  The balloon will slowly expand and "stand," though it will not stretch the balloon.
  5. The baking soda is a base and it reacts with the acid in the lemon juice to create carbon dioxide gas.  The gas has no place to go, so it expands the balloon!
Fizzy Lemonade {5 minutes}
Materials: large cup/pitcher, water, sugar, baking soda, lemon, knife, cutting board, large spoon, cups for students
  1. Cut open lemon and examine the inside.
  2. Squeeze the juice from it into the pitcher.  Add water. 
  3. Add a touch of baking soda.
  4. Discuss why the pitcher does not overflow like the mini-volcano.  (Unless you have too much in too small of a cup like pictured below.)
  5. Discuss what is making the bubbles and remind them of the volcano.  Does it remind the children of soda?
  6. Add a touch of sugar.
  7. What could we do with this mixture?
  8. Pour an ounce or two into each cup for the children to eat.  Have everyone drink the fizzy lemonade at the same time.
Review all the lemon science experiments that were completed.

Lemon science extensions: In addition, children could also use lemon juice for disappearing ink, apple slices, and non-edible fizzy bubbles (made with dish detergent, lemon juice, and baking soda).  What other lemon science experiments would you add?

Interested in more science?  Try our cold weather science experiment and germ experiment!  Also, be sure to investigate our Pinterest Science board.


~ Annette {This Simple Mom} 

2 comments:

  1. Another friend of mine had her son figure out how to make fizzy lemonade, and it was really quite funny.

    ReplyDelete
  2. All these experiments sound so fun, especially the fizzy lemonade one!

    ReplyDelete

Thanks for taking the time to leave a comment!