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MLA Full: "Watch Soap Grow!" YouTube, uploaded by SciShow Kids, 6 March 2018,
MLA Inline: (SciShow Kids, 2018)
APA Full: SciShow Kids. (2018, March 6). Watch Soap Grow! [Video]. YouTube.
APA Inline: (SciShow Kids, 2018)
Chicago Full: SciShow Kids, "Watch Soap Grow!", March 6, 2018, YouTube, 04:17,
Jessi and Squeaks just did a really cool and easy experiment: they put a special kind of soap in the microwave and made it grow! Now they want to do it again to check their results and figure out how it happened!

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Squeaks and I tried a new experiment today! [Squeaks squeaks]. OK, Squeaks is really excited to show you, so check out what happened! ♪.

How cool is that?! We tried this experiment because we heard that there’s a special kind of soap that looks like it’s growing when you heat it up in microwave. It was so fun the first time that we're going to try it again.

That's a big part of doing science — it's important to try experiments more than once to see if the same thing happens every time! The soap we're going to use is called Ivory brand soap, and we're using it because it’s made a little differently than some other soaps. [Squeaks squeaks]. Well, when this type of soap is made, it’s whipped and moved around really quickly, trapping air bubbles inside the soap.

If you've ever baked a cake and used an egg beater to make the eggs all fluffy, it's kind of like that! If you break open a bar of this type of soap with your hands, you can actually see the small pockets of air all throughout the soap, and that's where the bubbles were. But those pockets have more than just air.

They also hold tiny bits of water vapor. That's water in the form of a gas, and it's part of the air all around us. You can even feel it sometimes, when it's raining or very hot outside and the air feels kind of heavy.

And now, some of that air has been trapped inside this bar of soap! OK, let's see what happens to those gases when we heat them up. For this experiment, the first thing you should do is get permission and help from a grown-up, because the soap will get very hot.

Then, you'll need a bar of Ivory brand soap, a knife, a plate, and... ...a microwave to put the soap into! First, have your grown-up assistant help you cut the bar of soap into four small chunks. Make sure the soap is on the plate with a bit of space between each of the chunks.

Then, put the plate into the microwave for one minute. You and your grown-up assistant should keep an eye on the microwave, to make sure the soap doesn’t grow too much. Ready, Squeaks? [Squeaks squeaks] ♪.

Wow, it looks like the soap is really growing! Check out all the fantastic shapes it’s turning into as it changes! Wow, what a change!

Let's wait a few minutes for our soap explosion to cool down. Wow! What do you think made this soap act so strangely when we heated it up in the microwave? [Squeaks squeaks].

I think you might be right, Squeaks: it was the bubbles inside the soap! When the microwave heated it up, something started to change with the air and water vapor inside those little pockets in the soap. When the air and water heated up, that gave them lots more energy.

So they started moving around a lot to use up some of that energy! It's almost like when Squeaks gets really excited about something and he starts bouncing around a little! But those little pockets of air don't have much room in them.

So as the air and water vapor move around, they're trying to escape to somewhere they'll have more room. And that means getting out of the tiny air pockets in the soap. While the gases are getting more and more energy from the heat, the soap is getting softer.

Until little bit by little bit, the air and water vapor start to push out on the soap from the inside. And then, the soap starts to expand and grow into this awesome soap explosion! [Squeaks squeaks]. Ok, good idea, Squeaks!

It's cooled down enough now, so let's go ahead and feel it. It does still feel like soap, and I bet it’ll be even more fun to wash our hands now. I wonder if this would happen with soaps that don’t have air pockets trapped inside.

And what if we used smaller pieces of soap? If you try this experiment, we'd love to hear your results! Ask a grown-up to help you leave a comment down below, or send us an email at

Thanks, and we’ll see you next time, here at the Fort! ♪.