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The Kid Should See This

Aluminum foil boat floating on a sulfur hexafluoride sea

It’s not magic. It’s science! Sulfur hexafluoride (SF6) is a colorless, odorless gas that is more dense than air at 6.12 g/L (at sea level). This density is why you can pour it into a glass container and float a light-weight aluminum “boat” on its gas “sea.” Watch this 2007 demonstration at the Physikshow of the University of Bonn.

Update: Via @AlomShaha, please note that educators and science communicators are moving away from this demonstration for reasons of environmental safety. From Wikipedia:

“According to the Intergovernmental Panel on Climate Change, SF6 is the most potent greenhouse gas that it has evaluated, with a global warming potential of 23,900 times that of CO2 when compared over a 100-year period. Sulfur hexafluoride is inert in the troposphere and stratosphere and is extremely long-lived, with an estimated atmospheric lifetime of 800–3,200 years.”

aluminum foil boat
Check out related sulfur and gas videos in the archives.

via Quora.

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