Atmospheric pressure
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An aspirator is a device that removes gases from closed containers. This aspirator is removing iodine vapor from a filter flask. The filter flask is now connected to a metal can. The aspirator is turned on and after one minute, the can has collapsed significantly. Once air has been removed from inside the can, atmospheric pressure crushes the can and eventually squeezes it into a very much smaller volume than at the beginning. Atmospheric pressure is about 14.7 pounds per square inch, enough to crush a strong metal can or to support a column of water about 30 feet high.
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Portion with no voice-over
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This is a portion of the movie having the same video, but the audio consists of the sound of the experiment only, without the voice-over.
© 1997 Division of Chemical Education, Inc., American Chemical Society. All rights reserved.