Peeps in a vacuum chamber

Chief Scientist, Carl Nelson puts Peeps in a vacuum chamber to find out what happens when the air is removed from the fluffy candy.

The balloon and Peeps expand as the air pressure in the chamber is reduced by the vacuum pump. Peeps contain millions of tiny air pockets inside the gelatin/sugar mixture they made of. As the air expands inside the Peep, it pushes against the walls of the air pockets and eventually tiny rips and tears form between the air pockets that allows the air to escape. Once the air stops flowing out of the peep, the force exerted on the Peep relaxes a bit and it begins to slowly shrink. Allowing air to rush back inside the chamber further crushes the Peeps as the air slams into them.

Christina noticed that the Peeps felt cold when touched. From a thermodynamics perspective, the tiny air pockets inside do Work as they expand. The energy used to do this Work on the walls of the pockets reduces the internal energy of the air inside the peep and it’s temperature drops, thus cooling the Peep.

The shaving cream grows large for the same reason as the Peeps. When the air is suddenly returned to the chamber the foam is much more dramatically crushed since it has a much weaker physical structure than the gelatin/sugar mix used in the Peeps.

Imagination Station, Toledo’s hands-on science center, is a vital non-profit organization that is an integral part of Toledo’s economic, educational and social landscape. Imagination Station provides a critical layer of science enrichment by serving as an educational partner for teachers, schools and parents. It’s with a thoughtful blend of exhibits, experiences, education and excitement that Imagination Station is inspiring future generations of scientists in Northwest Ohio. With hundreds of hands-on exhibits and demonstrations, Imagination Station delivers a multi-sensory experience that’s as fun as it is educational.

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