Boyled Marshmallows

Purpose

Amusing demonstration of Boyle's Law.
 

Equipment

Vacuum pump with bell jar, marshmallows.

 

Suggestions

BRING YOUR OWN MARSHMALLOWS! Do not place the marshmallow near the pump inlet.
 

Images

i3-42

Description

A marshmallow is placed in a bell jar. As the air is pumped out of the jar the pressure inside becomes smaller and the little bubbles of air in the marshmallow increase in size, inflating the marshmallow. Eventually much of the air originally in the marshmallow is pumped aaway. When the air is let back in, atmospheric pressure compresses the marshmallow to a small fraction of its original size.
 

References

Operation and Maintenance Manual for E.M.E. Boyle's Law and Absolute Zero Unit, Educational Materials and Equipment Co. Operation and Maintenance Manual for E.M.E. Boyle's Law and Absolute Zero Unit, Educational Materials and Equipment Co. ◙Graph of Temperature vs. Pressure (with transparency). ◙Calculation Sheets, Performance Check (hand written).