Squishy Marshmallows: Reduce Air Pressure

A little secret is that the girls and I love squishy marshmallows. So, why not make an experiment using one of our favorite snacks. Your mouth does a happy dance from these light,  fluffy, layers of little air pockets that make your taste buds sing.

Squishy Marshmallow: Reduce Air Pressure
  • glass jar
  • big and small marshmallows
  • straw
  • modeling clay
  • cotton swab
  • food coloring
  • Premo clay
  1. drop some food coloring on a cotton swab. We put several pieces of paper towel to collect the excess
  2. Draw a face on your Marshmallow
  3. Place the marshmallow inside the clear jar
  4. wrap a clump of clay around the straw
  5. insert into the jar and seal it the best you can, adding extra clay if you need to
  6. Blow gently into the straw to make sure it is sealed
  7. Now, using the straw suck as much air as you can out. What happens?
  8. Release the air and see what happens to the marshmallow?


What we discovered

img_4672The experiment did not work and we have no idea why. Well, we couldn’t get it to work and myself and hubby both tried to suck the air out of the jar. The modeling clay kept caving in and would not seal no matter how much clay we added. We finally used Premo Polymer clay, which Belle and I use to make our jewelry. The jar would seal but we could not suck enough air out to get the marshmallow do anything. After several tries, we gave up and put it in the microwave, then ate it just for fun.


Science behind it:

img_4663When you suck the air out of the straw, you remove air from the jar. The air pressure surrounding the marshmallow is lower than the air pockets inside the marshmallow. When you remove the air, the air inside the marshmallow moves out and pushes the sides out. When you release the air back in the jar it squashes the marshmallow back down.

img_4669In essence, the volume of gas in the marshmallow increases when the temperature increases and then decreases as it cools down. The Exploratorium suggests not microwaving marshmallows for longer than 2 minutes, less you want a dark, stinky, burnt mess on your hands.

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About Chrissie

Follow our crazy journey across America as we visit roadside oddities, historical land marks and beautiful landscapes. I have ton of ideas and review educational products that will help you get the most on your home school adventure. We are an Unschool family that believes the world is our classroom and is teaching our children to self direct their education to a better future.

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