Grab the kids and try this experiment. Or don’t grab the kids and try this yourself.
It’s just as fun! All you need is a microwave and 1/4 bar of Ivory Soap.
The Ivory Soap Explosion Experiment:
You must use Ivory soap or it will not work. After all, Ivory soap is “The soap that floats!”
If you don’t already have a bar, go buy a pack. It’s very inexpensive for a 4 pack and you will want to do this a few times anyway. After you do it, you will want to start passing the extra soap around the neighborhood and telling everyone you know to try it – even people you don’t know. Not that I know from experience or anything…
Do not use a whole bar in the microwave!
Cut the bar into quarters…
…then place one quarter bar on a microwaveable plate, such as a paper plate.
(I have tried this with half of the bar and it got a little too big in there, FYI…)
Set your microwave on High for 1 minute, but it will probably only take about 30 seconds to see the full effect. It will start to grow in about 20 seconds. When it stops growing (or if it gets as big as your plate), turn off the microwave and let sit for a minute just in case it’s too hot. Take it out and touch it! It’s so cool. You will be the most awesome adult in the world for those 5 minutes. Promise.
Now do it again. (Because that is the first thing out of their mouths after they Oooo and Ahhh…)
If you are so inclined, the soap can be used again after the experiment. Just let the kids grab a chunk when they bathe or wash their hands.
For the science part of this and why this only works with Ivory Soap, here is the explanation from stevespanglerscience.com:
“Ivory soap is one of the few brands of bar soap that floats in water. But when you break the bar of soap into several pieces, there are no large pockets of air inside. If it floats in water and has no pockets of air, it must mean that the soap itself is less dense than water. Ivory soap floats because it has air pumped into it during the manufacturing process.
The air-filled soap was actually discovered by accident in 1890 by an employee at Procter and Gamble. While mixing up a batch of soap, the employee forgot to turn off his mixing machine before taking his lunch break. This caused so much air to be whipped into the soap that the bars floated in water. The response by the public was so favorable that Procter and Gamble continued to whip air into the soap and capitalized on the mistake by marketing their new creation as “The Soap that Floats!”
Why does the soap expand in the microwave?
This is actually very similar to what happens when popcorn pops or when you try to microwave a marshmallow. Those air bubbles in the soap (or the popcorn kernels or the marshmallow) contain water. Water is also caught up in the matrix of the soap itself. The expanding effect is caused when the water is heated by the microwave. The water vaporizes, forming bubbles, and the heat causes trapped air to expand. Likewise, the heat causes the soap itself to soften and become pliable.
This effect is actually a demonstration of Charles’ Law. Charles’ Law states that as the temperature of a gas increases, so does its volume. When the soap is heated, the molecules of air in the soap move quickly, causing them to move far away from each other. This causes the soap to puff up and expand to an enormous size. Other brands of soap without whipped air tend to heat up and melt in the microwave.”
I hope you try this…it’s really a fun thing for the kids, but I’m telling you — you’ll be the hit of your office if you try it there, too!