Slime

Whenever SPICE goes out and does a "family science night" show at a local elementary show, it usually requires some sort of hands-on type of experiment for kids to do. One of the easiest ways to accomplish this is for the kids to make some slime. It's easy, quick, fun, and o so messy, which everyone except the parents love.

We usually do two or three different types of slimes, which is a great way to teach kids about polymers (long chains of molecules), and how lots of different things are made of them, like clothing and plastics.

One type of slime is the kind that most people usually made during elementary or middle school. All you do is get some borax (a detergent) at the store, mix it with some water to dissolve it, and then mix in some Elmer's glue. This one is really easy and cheap, and kids can put in a few drops of food coloring and put it in a bag to take home.

One of my favorite "slimes" is just cornstarch and water. (2 parts cornstarch to one part water). If you watch Mythbusters like I do, they did this one on their show. When you mix it in the right ratio, you get a mixture that is liquid when you pour it or let it rest, but when you apply a force to it (poke it, stir it, etc) it acts like a solid. Its not really a polymer, but what happens is that the starch molecules are very large and branched, so when you apply force, the molecules are shoved together and they can't move past each other, so the mixture acts like a solid. If you don't apply force, the molecules are able to slowly move past each other, so the mixture looks like a liquid.

Try it!