The phenomenon is called "supercooling"
Exactly how and why it occurs is the source of all sorts of debates, because what is going on is so far outside normal human preconceptions of what "freezing" and "melting" are, that when you start pushing the physics of freezing and melting to their usual boundaries, weird things that most people can't explain begin to happen.
Here are a couple websites about it:
http://en.wikipedia.org/wiki/Supercooling
http://www.armory.com/~spcecdt/fun/supercool.html
In all likelihood, what is happening is a combination of things coming together at once. While the soda remains sealed, there is a lot of CO2 both presurizing the contents and in solution in the soda mixture. When you open the bottle/can, the CO2 rapidly escapes which:
(A) reduces the pressure, thereby causing the temperature to drop,
(B) the dissolved CO2 begins to come out of solution, creating better nucleation sites for the freezing to begin,
(C) the dissolved CO2 in water was forming a chemical commonly called "carbonic acid" (H2CO3), but as the CO2 escapes from the solution, the solution returns to just being sugar water. I can't find any data on the melting point of carbonic acid but my bet is that it is lower than that of sugar water (many acid solutions in water have a lower melting point than that of pure water, and sugar water definitely has a higher melting point than pure water), so as the solution stays at the same temperature or slightly decreases in temperature while the melting point of the solution becomes higher, the mixture transitions to a state in which its temperature goes from above the melting point to below it, and the mixture freezes.
(D) as the CO2 gas inside the bottle/can is exchanged for the outside air, particles of dust etc. may enter and provide better nucleation sites for the freezing to start at.
2006-11-08 05:46:35
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answer #1
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answered by Mustela Frenata 5
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It was cold enough to freeze, but didn't have access to oxygen. You open the bottle, oxygen goes in, and BAM! Frozen soda!
2006-11-08 13:42:00
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answer #2
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answered by dph 4
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i dont know but after i freeze mine a little bit, i open it and its slushy.
2006-11-08 13:42:41
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answer #3
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answered by MiaDiva28 6
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