Invisible Water - Sulfur Hexafluoride |
We had such a great response to our post about ferrofluid a few months back that I thought I would share this video showing the effects of a gas that is six times more dense than ambient air. In the video after the jump a light boat made out of tin foil floats on top of sulfur hexafluoride contained in an aquarium, and the gas is actually able to be “scooped” like water to fill the boat and make it sink.
My first thought was that the sulfur hexafluoride might be toxic, but according to Wikipedia the gas is colorless, odorless, non-toxic and non-flammable. The gas is actually dense enough to even float some light woods. To give you some reference; air is 784 times less dense than water compared to the 6 times of sulfur hexafluoride, and water is about 2.5 times less dense than dirt in case you were wondering.
Another interesting thing about sulfur hexafluoride is that it has the opposite effect on your voice than does helium. Inhaling it and speaking will make a persons voice a very low pitch, although we do not recommend doing this. Lungs like air, not sulfur hexafluoride.
Check out the video:
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I believe the compound is sulfur tetrafluoride, not hexafluoride. Sulfur Hexafluoride is not nearly as dense as water as SF4 is nearly 2x. Likewise, SF4 is highly toxic as it decomposes in water and forms hydrofluoric acid…
Actually it is sulfur hexafluoride, search for it and there are numerous entries (wikipedia for example has a lot of physical properties.)
One thing to be aware of if using SF6 to do demonstrations: it has a green house gas/climate change capacity order of magnitudes greater than CO2 or H2O. Be careful to only use a little and even though its dense some does escape to the atmosphere.
watch mythbusters on discovery channel 8-13-08 9pm eastern time…they are doing a whole thing on “invisible water”
it is sulfur hexafluoride and it is sweet now where do u get it at