Science Activity: Boro Slime

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Have you ever watched people throw slime at each other on television? In fact, that slime is actually a harmless substance. It's even sold in toystores! You'll make some slime of your own in this activity, but you won't be throwing it at anyone. Instead, you'll be studying it like a scientist does, since slime is a type of matter that behaves very strangely.

1. Get Ready

Box of Borax or Boraxo laundry booster
Container of white, nontoxic Elmer's Glue-All (7.58 ounce/225 milliliter size)
Two small plastic bowls that can each hold at least 2 cups (about 1/2 liter) of liquid
One larger plastic bowl that can hold at least 5 cups (more than 1 liter) of liquid
Water
Measuring cups and spoons
Stirring spoon
Paper and pencil
Newspapers
Access to a sink

2. Do and Wonder

Cover your work surface with newspapers.

To make the slime, you'll need to prepare two liquids: (1) a glue mixture and (2) a Borax solution.

First make the glue mixture: Pour the full container of glue into one of the small bowls. Then refill the empty glue container with water, and add that water to the bowl. Stir the glue/water mixture thoroughly, and then pour it into the larger bowl.

Next make the Borax solution: Pour 1 cup (about 250 milliliters) of warm water into the other small bowl. then stir in 2 teaspoons (about 10 milliliters) of Borax. If all the Borax dissolves, stir in a little more until you see Borax crystals at the bottom of the bowl.

Now make the slime: Slowly add the Borax solution to the glue mixture. Stir the mixture as you pour and then for another minute or two. Congratulations! You have made Boro Slime. Remove it from the bowl, and squeeze out the excess liquid.

Test the Boro Slime to discover its properties. Try to poke, stretch, and pour the slime. Invent other tests and try them, too.

Find out if the Boro Slime can bounce. Form a tiny ball of slime by pinching off some and rolling it in your hand. Predict how high the ball will bounce if you drop it from a height of 20 inches (about 50 centimeters). Drop the ball from this height, and compare the results with your prediction.

3. Think and Write

In one paragraph, tell how you tested your slime and what you learned about its properties.
In another paragraph, invent a practical use for the slime you just made.

Explanation

Slime is a special kind of fluid. Like all fluids, it takes the shape of its container. It also can be slowly poured from one container to another. Slime changes its behavior when you apply a force to it. Pushing, pulling, or striking slime makes it act like a solid. Scientists have a name for any fluid that acts in these very strange ways: It's called a non-Newtonian fluid. Isaac Newton was the first scientist to write about this type of fluid, which is how it got its name.

Safety Hints

Don't taste the slime.

Thoroughly wash and dry all your equipment when you're done.

Dispose of the cups.

Wash your hands after completing the activity.