Kate's Corner: Pepper magic

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In this edition of Kate's Corner, I'll explain the science behind a simple experiment that your friends will think is magic.

This one involves three things you can easily find in your kitchen.I have a bowl of water, some pepper, and dish soap.

First thing you do if shake a generous amount of pepper onto the water. The more the better. Finally, put some dish soap on your finger, dip it in the water and watch the magic.

The pepper magically shoots away from your finger to the edge of the bowl.

So why does the pepper magically spread out? Well, it all has to do with something called surface tension.

Surface tension is a property of the surface of a liquid that allows it to resist outside forces. Surface tension is caused by cohesion of similar molecules and is responsible for many of the behaviors of liquids. Another example of this property in real life is when you see a mosquito sitting on top of water and not falling through.

Most dish soaps lower the water's surface tension so it spreads out and takes the pepper with it.