Bugs wrote:This one is really cool, but tricky. Ideally you need a smooth-sided bottle of very pure, fizzy water (I've got it to work with a bottle of Sprite in the past). Anyway, chill your fizzy liquid down to just above freezing; something like 1-2 degrees C should be fine.
When you open the bottle, bubbles will form as normal with two effects. Firstly, the expanding gas will help cool the liquid further, taking some parts of the liquid below 0 degrees. Secondly, the bubbles act as nucleation sites for the formation of ice crystals. Result: when you open the bottle lid, the whole thing freezes solid within a few seconds. You see a small core of ice forming, then corkscrewing out to spread the length and breadth of the bottle.
In principle, you should be able to take very pure water in a smooth-sided vessel down to a few degrees below zero without any ice forming. This is becasue ice crystals can't easily form unless they have some irregularity to act as a seed / mucleation site. If you then introduce a suitable irregularity - drop in a grain of sand, or tap the glass to create small vortices - the ice will form around it and, again, the whole thing will freeze solid in seconds. It's tricky though, because the water needs to be very clean and in an almost perfectly smooth vessel.
I did that in a hotel a couple times... If you take the bottled water there and don't open it, it can sometimes work. Very tricky though.
I managed to get it so I could shake a bottle and reliably turn it to ice.
Once I tried pouring a bottle out and it started solidifying when it hit the sink and I ended up with this awesome tower of ice.
Also, I tried drinking it because I didn't realize it was superchilled. It was very odd feeling, since it was water and turned to slush in my mouth.
Anyway, Match rockets are fun, as long as they don't spurt like an inch and land on your hand.
If you go vacationing, you can demonstrate air pressure.
I live in winful MA, and went out to Yellowstone. While I was there, I took an empty bottle of water and put the cap on, then took it home. When I got there, it was completely crumpled by air pressure.
O is fun.
Wait. With a SPOON?!