Chemistry for Kids: Lesson 3

Materials:
1 packet of microwave popcorn

Take the plastic wrapper off some microwave popcorn. Throw the wrapper away.

Weigh the bag. How much does it weigh? ___________________

What do you expect to happen to the weight after the popcorn has popped? Why? ______________________________________________________

______________________________________________________

Pop popcorn.

Weigh the bag again. How much does it weigh? _______________

What happened to the total weight? Why?____________________

______________________________________________________

______________________________________________________

Eat popcorn.
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For the parent: In the last experiment we learned that matter is not destroyed, yet this experiment seems to prove otherwise. Let them wrestle with the seeming contradiction. If you need to step in with a hint, you can ask them if they remember what happened when they opened the door of the microwave. Did anything come out besides the bag of popcorn?
The point of this experiment is to show that sometimes it will seem that matter has been destroyed in a chemical reaction. Since we know that cannot be so, there must be another explanation. Usually the alternate explanation has to do with some fault in the setup of our experiment. In this case water that was inside the popcorn kernals became steam. In our experiment, we did not capture the steam, but that doesn't mean that it wasn't there.