In a plastic drink cup, mix ¼ cup liquid starch with ¼ cup Elmer’s glue and stir with a Popsicle stick until completely blended. Use hands if necessary to blend. Hands can be washed with baby wipes or water. Have the Brownies answer the following questions about solids and liquids. Store the silly putty in Zip Lock bags after experiment. Brownies can take the silly putty home.

Explanation:

Silly putty is a fun toy that many children have played with before – but most do not know the science behind it. Silly putty is a colloid. Discuss the different states that matter exists in. Most things exist as a solid, liquid or a gas, but sometimes a substance doesn’t seem to fit well in any of these categories. Is silly putty a solid or a liquid? Actually, it’s both. Silly putty is a colloid.

Colloids are mixtures, which consist of one substance suspended in another. Some other examples of colloids are: smoke, fog, mayonnaise, and meringue.

Questions:

Name one liquid, solid, gas?
How can water be a liquid, solid, gas?
What happened to the liquid starch when it was mixed?
Is this a liquid, solid, or gas?
What happens when you pull the putty slowly?

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