Ivory Soap Science Experiment

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Science experiments for kids are always a huge hit at this house.

Anything hands-on with a cool reaction — like our fizzy baking soda hearts or milk and dish soap science experiment — is always a great way to start our day and lead into bigger questions about how things work.

This week we tried an awesome Ivory soap microwave science experiment for kids to explore how air expands when it heats up!

Ivory soap microwave science experiment for kids: A great way to learn about what happens to air when things get hot! We love science experiments for kids!

You only need three things to conduct this experiment:

  • microwave
  • microwave-safe plate
  • bar of Ivory soap

While this experiment could potentially work with other brands of soap, Ivory is recommended as it is known for having extra air “whipped into” the final product. If you try it with another brand of bar soap, please let us know how it turns out!

Simply unwrap your bar of soap (a good fine motor activity) and let your child explore the soap while describing the activity that you have planned. Explain that this bar of soap has little pockets of air in it and that air expands when it is hot, and takes up less space when cold.

Ask them to hypothesize (guess) what will happen to the bar of soap if you were to put it in the microwave.

(Encourage them to support their hypothesis by linking their guesses to what they observe about the bar of soap and what they have previously observed with the microwave.)

Place the bar of soap on a microwave-safe plate and place in the microwave on high for 1-2 minutes. I personally found our soap stopped expanding after 1 minute, but microwaves can vary.

Observe the changes that the soap goes through, using as much descriptive language as possible.

Cannot believe how cool this microwave ivory soap science experiment for kids turned out!

Take out the plate and once the expanded soap has cooled down, allow your child to carefully explore it (keep in mind that while the outside of the soap may be cool, it could still be very hot towards the center. I would suggest exploring using “tools” rather than fingers.

Ask your children to interpret or make sense of what they have observed and draw conclusions.

Ivory soap microwave science experiment for kids -- a great hands-on way to learn about weather! We love science experiments for kids!

This easy and safe science experiment for kids is such a great way to introduce learning about weather or discussing how microwaves work. (And practice going through the steps of the scientific process.)

You can then use your soap to make homemade laundry detergent, or clean mud with the kids!

Would you try this science experiment with your kids? What other science experiments for kids have you tried?

For more fun science experiments your kids will love, check out our Straw Rocket Science experiment and Magic Milk Science experiment.

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  1. Looks like fun! I think it would be fun to expand this experiment and try other brands of soap, recording the results. I’m definitely going to keep this one in mind for when we need something to do this summer.

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