Exploding Soap

Sometimes it is challenging finding projects that work for a veriety of ages, but in my experience very few people under the age of 18 (40 for boys) can resist the words "hey, you wanna go blow something up in the microwave?" This is especially true if the words are spoken by an otherwise reasonable adult.

I saw this exploding soap trick on Pinterest the other day and I figured it was worth a shot. Ivory soap (it really does have to be Ivory) is super cheap and I always have some on hand. We put it in the microwave for a little over a minute. I set the timer for two minutes, but we watched it and pulled it out early.

I explained that this was a demonstration of Charles' Law, that the volume of gasses increases when they are heated. It works similar to popping popcorn. The air and the water in the soap expand when heated and cause the soap to foam.

After we microwaved the soap I put it in the food processor with some water, coloured it and added some essential oil. Cheyenne picked blue and peppermint, Isabella picked red and lavender and James picked green and geranuim.

We pressed the soap into cookie cutters and they each got their own little souvenier of our science project. It wasn't nearly as messy as it looks.