The Pepper and Soap Experiment for Kids: Easy Science Activity To Do at Home

4/12/20 - By Rosalind Muggeridge

Show kids the importance of washing their hands while they learn about the surface tension of water. One of our 63 Easy Experiments for Kids Using Household Stuff, this experiment went viral when the coronavirus hit and teaching kids about proper hand washing became essential.

This super easy experiment is fun for all ages—especially the toddler set—and it couldn't be more simple. All you need is water, black pepper, and dish soap.

Read on to learn how to chase the "pepper" germs away!

You will need:

A shallow bowl or dish (a pie plate works well if you have one), water, ordinary black pepper, and some liquid dish soap.​

Step 1

Cover the bottom of your shallow dish with water.

Step 2

Sprinkle black pepper across the surface of the water. Note how the surface tension of the water causes the pepper flakes float.

Step 3

Stick your finger in the center of the dish; did anything happen? Not much right? You probably just got some pepper flakes stuck to your finger. Now imagine that the pepper flakes are germs.

Step 4

Now dip the tip of your finger into the liquid dish soap—you don’t need much.

Step 5

Now stick that finger into the center of the dish. What happens? Your soapy finger chased those pepper flakes to the edges of the plate! Dish soap is formulated to break the surface tension of water, which is why it is so effective on greasy, dirty dishes. And it wasn’t until you added soap to the bowl that those "germs" were chased away. This is the reason grown-ups are always nagging you to wash your hands with soap!

Find this science experiment and more ideas in our 63 Easy Science Experiments for Kids article or peruse our STEM Guide for Kids for more hands-on experiments.

Photos by the author