Why do some liquids freeze after removal from freezer?

Beer does for example.

I think that it has to do with the nuclei around which the ice crystals form. While the beer is intact in the freezer, it is below freezing point, but there is not enough contamination to form ice. If you open it and the bubbles start to form, this serves as contamination.

It's not the pressure, cause the same thing happens to liquids that have the same pressure as the environment (the room in this case). It happens even with water, given the right circumstances.

Same thing would happen if you supercool some purified liquid (say distilled water or something) and throw some salt or sugar in - it would freeze in seconds.

Check this out!

http://www.youtube.com/watch?v=fSPzMva9_CE

Cheers :)

Everyone here says it's pretty painless. Well I guess they didn't have very big warts. I had a wart the size of a quarter on my foot that the doctor used N2O to freeze off. It felt like my foot was going to explode. Which, after the blistered swelled to the size of a tennis ball a few days later, it did. I didn't cry because that would have been embarrassing for a 12 year old, but I wanted to, it hurt soooo bad. I just kept thinking about that scene in Terminator 2 where the T-1000 gets frozen in N2O and shatters!

To freeze a liquid must have motion in order for the molecules to ''fit together'' in the final stages of freezing. Undisturbed liquids will go below their freezing point and remain liquid until the necessary motion is provided (you removing the container from the freezer). The effects as you have observed, are nearly instantaneous.

If you notice when you take the cap off, you hear a hiss. That is because there is a higher pressure in the bottle than in the room and liquids at higher pressure require a lower freezing point. When you take the top off, the pressure in the bottle lowers and the liquid then freezes.

huh? why that's incredible! look, sweetie. on this planet, in this part of the globe, under that yellow orb, called the sun, nothing of this planet, natural or otherwise, will freeze AFTER being removed from the freezer. we do have stuff that can not freeze as the molecular structure doesn't support it, some freeze just looking at it after it's placed in a very cold area and some that can not be frozen and defrosted and have it retain it's original shape/form but there is nothing that i know that freezes after the fact. nothing natural anyway but you keep smoking whatever you're smoking, save some for me. i'll be right over!

because of the motion of the molecules. when in the freezer the liquid molecules have no motion and once you take them out the rest are exposed and they freeze instantly ,

liquid when cooled freezes at zero and then defrost at -4 then feeze again, you are probably taking them at -4.. then they warm to zero and freeze

it freezes but the icing effect happens when you disturb the liquid and the sugar molecules freeze

WOAH! thats wicked! ive never heard of that....what brand of sweetened tea i would like to do some experements.

Alchohol never freezes thats why I just drink that!