How can you expand marshmallows
Use the power of emptiness!
Warning! Only under adult supervision
Equipment
- vacuum chamber;
- marshmallows.
Step-by-step instructions
Seal some marshmallows in a vacuum chamber, make sure the vacuum chamber valve is closed, and pump the air out with a piston. The marshmallows expand! Open the valve and watch as the marshmallows deflate.
Scientific description
When you lift the pump handle, air from the vacuum chamber is drawn into the syringe. When you lower it, you force the air out into the atmosphere. The valve system lets air out from under the hood but doesn’t let it back in. Marshmallows have a porous structure – they contain innumerable bubbles filled with gas. In pumping air out of the chamber, you lower the pressure inside. When the pressure inside the bubbles is greater than the pressure outside them, they begin to increase in size, inflating the marshmallows. If you open the valve and let air back into the chamber, everything will deflate: the atmosphere will squeeze the inflated bubbles to their original size, and with them, the marshmallows themselves!
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