Great Balls of Goop


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Experiment Category: 


Explore chemical reactions as they create their own goopy polymer.

What You Need: 

  • White craft glue
  • Craft stick
  • Borax
  • 2 paper cups
  • Water
  • Measuring spoons
  • Clean-up materials (paper towels, soap)
  • Zipper top plastic baggies or small plastic container

To Do and Observe: 

1. Pour 1 tablespoon of white glue into the first paper cup.2. Add 1 tablespoon of water and stir with stick until mixed. Set this cup aside. 3. In the second paper cup, mix 1.5 teaspoons of borax and 4 tablespoons of water. Stir well.Before the borax settles to the bottom, use a tablespoon to scoop out ONLY one spoonful of the water and borax mixture.4. Pour the borax solution into the cup that has the glue and water mixture.5. Stir with stick. If the mixture doesn’t quickly gel, add another tablespoon of the borax mixture and stir again.6. Remove the gel from the cup and roll it in your hands until the substance firms up.7. Now it’s ready to play with!8. To save your goop, place it in a zipper top plastic bag.

What's Going On: 

In this activity you mix white craft glue and borax solution together to produce a surprising new material: GOOP! Sometimes when two substances are combined the properties of the substances change. A physical or chemical reaction is taking place when this happens.White craft glue is a type of polymer called polyvinyl acetate. Polymers are large molecules made up of many smaller molecules, or monomers. These are arranged in a strand-like fashion. When the borax solution is added to the glue, the molecules of the borax bind up the glue “strands” so that the glue no longer flows freely.The properties of this new substance are unlike the original glue or borax solution. The “goop” behaves in an unusual way; it has some characteristics of a liquid and some characteristics of a solid. Goop may remind you of a well know commercial product called Silly Putty.  

Parent/Teacher Tips: 

For Younger ChildrenUse old newspapers to cover the tables. Depending on the age of your students you can make a large batch of the Borax solution for the children to use, ask children to describe the goop’s physical properties. Is it a liquid? Is it a solid? Why? Optional variation: Use food coloring to make the goop different colors.