Could someone explain this to me? I was freezing water bottles for a few hours (4 or so), and picked a water bottle up out of the freezer. It was clear; there was NO ice in it whatsoever. As I was walking to my room, I noticed the entire center of it suddenly froze. The ice was not hard, it was slushy. It came almost instantly, but you could notice a top to bottom movement. It was not pressurized, and it is generic spring water. The bottle was never opened.

 

A video is available here. http://dnpen.com/water.avi

 

Could someone please explain what exactly happened here, how it happened, etc?

It had got cold enough to freeze but aparently quite slowly, so the particles weren't moving all that much so they didn't get a chance to move into thier new structure until you shook it up.

It was probably supercooled, and the disturbance allowed to freeze. Once a nucleation site was provided, the freezing propagated from there.

i remember watching videos of some guy showing the same effect in his garage. i didnt watch yuor video, but i hope its actually your video, and not the same one i saw.

I agree with swansont, there are many videos showing supercooling on the Internet.

 

Here are some explanations:

http://home.howstuffworks.com/question290.htm (incl. a video showing the supercooling and then crystallisation of sodium acetate)

http://en.wikipedia.org/wiki/Supercooling

 

And here's some more videos:

http://f0rked.com/articles/supercooling

 

Once a nucleation site was provided' date=' the freezing propagated from there.

[/quote']Just incase anyone doesn't get that it means that once it starts freezing (ie. turning into a solid) all of it will start turning into a solid. The starting can occur by stirring or shaking. If it starts freezing at the top then the top will freeze first and then the frozen effect will spread down the container (ie. it is ordered, random bits don't just solidify by themselves).

I have seen the same thing happen with beer. You put the beer in the freezer for a quick chill and forget about it for many hours. The beer looks like ice cold liquid. But when you open it, it fizzes over and turns to slush.

I always thought it had to do with pressure.

As the water cannot freeze because when water becomes ice it expands but because it is in an air tight container the reaction cannot take place. But once you open the bottle or can not it possible even though the outside is warmer.

I have seen the same thing happen with beer. You put the beer in the freezer for a quick chill and forget about it for many hours. The beer looks like ice cold liquid. But when you open it, it fizzes over and turns to slush.

Carbonated drinks are a different breed, and can be subject to the following scenario: You have dissolved gas, which gives you some freezing point depression, which for beer is already lower because of the alcohol. When you pop the top and the CO₂ comes out of solution, the freezing point rises, and now the temperature is below freezing, so the beer (or soda pop) freezes. (You may have supercooled it too, and the bubbles contribute by giving you nucleation sites, but that's not necessary)

I always thought it had to do with pressure.

As the water cannot freeze because when water becomes ice it expands but because it is in an air tight container the reaction cannot take place. But once you open the bottle or can not it possible even though the outside is warmer.

 

The freezing point does not, IIRC, vary much with pressure, so it should be possible to form ice at the slightly raised pressure you'd have in the container, which might break. All this is moot if there's an air bubble that could contract.

someone told me u must use pure water or bottled water as opposed to tap water to do this, where they correct?

someone told me u must use pure water or bottled water as opposed to tap water to do this, where they correct?

 

Probably. Tap water usually has impurities that would act as nucleation sites and would tend to prevent supercooling from happening.

DucoNihilum, did you use pure water or tap water?