Microwave soap with Fizzics Education | Kids Science Experiments


Have 10% off on us on your first purchase - Use code NOW10


Soap in the Microwave?

Soap in the Microwave?

Follow FizzicsEd 150 Science Experiments:

You Will Need:

  • A microwave
  • A microwave-safe bowl.
  • Household soap, wet soap works best. So use an old bar of soap from the shower.


Soap in the microwave science experiment - materials needed
1 Soap in the microwave science experiment - soap in the microwave

Place the bar of soap in a microwave-safe dish and zap it in a microwave on high for between 30-60 seconds.

2 Soap in the microwave science experiment - beginning the experiment

You may need longer for low power microwaves.

3 Soap in the microwave science experiment - soap after 90 seconds

Watch as a foamy mass grows from the soap! (Careful; do not touch until the soap is cool).

4 hand with flame around it without injury
5 Teacher showing how to do an experiment outside to a group of kids.

Online courses for teachers & parents

– Help students learn how science really works

Orange read more button

Why Does This Happen:

The water inside the soap is undergoing a phase change from liquid to water vapour and expanding. The foamy effect comes about from the expansion air bubbles trapped inside the soap. By heating the soap and expanding the water and air inside, you end up with this lovely warm soapy foam.

Variables to test

More on variables here

  • Which soap bars work the best?
  • Does it matter if you change the power setting of your microwave?

Learn more!


Leave a Reply

Your email address will not be published. Required fields are marked *

This website uses cookies to improve user experience. By using our website you consent to all cookies in accordance with our Cookie Policy.