Toy Chemistry

Today's challenge is to mix two liquids together to form a gooey solid that you can mold and stretch into weird shapes. This is chemistry at its craziest!

  • Target Age: 8-10
  • Skills/Subjects: Science
  • Related Episode: Episode 318: Just Toying with Ruff


1. Get what you need:

  • 2 tsp. white glue
  • 1/4 tsp. borax
  • 4 tsp. water
  • Food coloring
  • 2 clear plastic cups
  • Measuring spoons
  • Plastic spoons
  • Plastic zip-lock bag for storage
  • Plastic knife

2. Mix the ingredients:
In a cup, mix 2 tsp. of water with 2 tsp. of glue. Then add 2 drops of food coloring. In another cup, mix 2 tsp. of water with 1/4 tsp. of borax.

3. Combine the mixtures:
Pour the borax mixture into the glue mixture and stir. When the two are mixed well, what happens? Take the goop into your hands and play with it.

4. Experiment and make observations:
Does your slimy goop act more like a liquid or a solid-or a little like both? Find out all the things it can do: try to stretch it, bounce it, flatten it, twist it, roll it, jiggle it, rip it apart, or use your knife to cut it into shapes. Does it keep its shape if you leave it alone for a while?

5. Safety Tips:

  • Keep mixtures away from clothes, eyes, and mouth.
  • Goop should not touch fabric or paper, only hard surfaces, since it sticks to things easily.


You just created a polymer. Many polymers are flexible plastics, like balloons, plastic water bottles, and the soles of your sneakers. But so are gelatin and nylon windbreakers. Some polymers, like a skateboard wheel, are strong and hard, yet flexible enough to absorb shocks and allow for a smooth ride. Other polymers, like chewing gum or the slimy goop you just made (which contains mostly water), are fluid and stretchy.

How did you make a polymer? Combining the borax and glue mixtures caused a chemical reaction. By themselves, glue molecules move about freely (until they dry). But when you add borax, it binds the slippery glue molecules together in a web, so they can't move around as much. Borax turns the watery glue into a denser, more rubbery substance.

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