Supercooled Water

Happens with hot water too... I remember seeing a 'get paranoid about something new' type newsstory a few years ago about people getting injured by microwaved liquids.... it seems that you can microwave water to above the boiling point, but sometimes it won't start a bubbling and steaming until it is shaken slightly or a spoon or something is inserted to stir.

I remember doing an experiment along those lines on a very cold day at school in my younger days.

The coolest experiment though was to put a styrofoam cup of cold coffee in the middle of a bowl, then pack ice all round it and put it in the microwave for a minute. When finished, the coffee was hot, but the ice had not melted at all.

Water seems to be a substance that behaves strangely!

Same thing works with a bottle of unopened Coca-Cola. Put it in the freezer for an hour or two, then open it, instantly turns to slush.

Same thing happened to me all the time when I still had a fridge in my basement. We kept bottled water down there and the fridge was notorious for getting extremely cold. Head downstairs for a bottle, open it up and have that first sip, and it would have a large core of ice by the time I got back upstairs again. I always thought it was the change in pressure that caused the reaction.

I find it difficult to believe you'd be able to recreate the expiriment in a freezer, since the freezer mechanism would make it vibrate, thus disturbing the water. That could be why it worked so well in this guys garage. No movement. Won't work in CA,anyway, too many earthquakes! 😛

I don't think it has to do with impurities, as someone else speculated I think it is related to pressure. I remember this happening with new glass jugs of Apple Cider that were left outside before thanksgiving. I lifted it onto the table (thus disturbing it obviously,) and then popped the top, at which point the entire 2 gallons froze up in about 2 seconds. Pretty cool.

I get an "error downloading codec." Anyone know why?

You can get the same effect with super-saturated solutions - carefully dissolving something into a liquid, more than it should be able to dissolve. Tap the beaker and it goes *clink* and there's crystals. Most crystals like to have a 'seed' to form around, which is why all snowflakes have a tiny particle of dust in their core. Once they have something to catalyze crystal formation, then all the molecules fall into place as fast as possible.

It's all science-y and stuff, and makes for a good demonstration in chem class when you don't have any magnesium around.

OH NO!!! It's ICE-NINE!!!

I've seen still water not freezing quite a lot, but every time I've told other people they never believed me. Now at least I have a URL to point to. Thanks. 😊

Citizen, maybe you don't have a media player that can view the videos.

Yeah, I used to do this when I was really really really bored in very cold climates. Take a bucket of water, let it sit outside for half an hour or so on a very calm, cold day, and then go up to it and tap the side of the bucket. It would make a loud snap!!! noise and freeze solid. Or if a slight breeze sprang up, or a snowflake fell in it, the same would happen. So it's not a matter of pressure in all cases. It has to be very still and very cold, though. And it's fun to direct somebody to that water to wash up or cook with:

"Hey, go wash these dishes in that basin."
"Okay, you mean this bas-" SNAP!!! "Aaaaaaah!"

And I have also been attacked by cups of water that have been microwaved, and then came bubbling out of the cup when I picked it up. That's not much fun.

We did a cool experiment with the super saturated liquid in high school. Heat a container of water to around boiling and dissolve a large quantity of salt or sugar in it, but not so much that there were any stray crystals still in crystal form. Then take the container outside and set it in the snow for an hour or so. The salt/sugar does not recrystalize until you drop that "seed" crystal that Robin mentioned in and the it all recrystalizes at once. Pretty neat to see.

This probably won't work in the freezer, as the temperature is always below 0. To supercool something, you need to cool slowly and evenly, otherwise you get a colder spot that will then freeze.
With the microwaved water, it can be very dangerous, as if the superheating is too high, the liquid will boil explosively, and probably cause severe burns. That is why you're meant to let heated liquids stand for a couple of minutes

"Happens with hot water too..."

Happened to me (a long time) back when we had our first microwave. I stuck a mug full of cold water in the microwave and heated it up.

After a couple of minutes the microwave 'pinged' and I took it out. The water wasnt bubbling, but as soon as I dropped the spoon in, it burst into bubles. So violently in fact that the water shot out and scalded me... :(

I have a small fridge out in the garage, and I experience the same "phenomenom" with water, soda, beer, actually anything liquid in the fridge. I like my beer at 32 degrees and have a thermometer in there to regulate the temperature on a regular basis. Being out in the garage where the room temperature is not regulated, somtimes when it gets cold in the garage, the temperature in the fridge will drop slightly below freezing, and when you open any beverage, bada-boom, bada-bing, instant slush or ice. I agree with the one fellow who says he don't think it's impurities, it's change in pressure...

not sure about "supercooling" but "superheating" works as described below.

Tap water, when put in the microwave will boil once it hits boiling temp, due to the impurities...Distilled water, with it very low if not nonexistant levels of impurities will not...waiting until impurities are introduced to release it's energy in one large release...which I speculate is what Richard@home experienced when he dropped the spoon into the microwave heated water. Richard didnt say that he was using Distilled water but I venture that it was some sort of purified water rather than tap.

Nope, plain old tap water Chuck. I can't say for sure if it was 'superheated' - I can only relate my own experiance. Note: I've done loads of cups of coffee in the microwave since then and never seen this behaviour since...

When you make coffee, I assume you add the coffee before heating. This will introduce nucleation sites.
In the case of carbonated/fizzy drinks, the presence of dissolved carbon dioxide will inhibit the crystalisation of water into ice. This is because the solubility of carbon dioxide in ice is almost zero (This is why it is almost impossible to make clear ice cubes in an icecube tray). In order for the water to freeze, the carbon dioxide must come out of solution. This will occur when the bottle/can is opened, and the pressure, which keeps the carbon dioxide in solution, drops.

You know, we keep our water bottles out in the garage, and when it was below freezing last year, I had this problem. I thought I was totally nuts, but nope, just science. 😊 Very cool.

As soon as it goes down below freezing again (it's 1 deg above here today) I'm going to try and get it to happen again.

I tried doing this today, since it was rather far below freezing, but I couldn't get the water still enough. I'll try it again later sometime, and see if I can get it on my camcorder.

The time I had an innocent-looking cup of water bubble over after being microwaved, it was nothing but tap water. No coffee, no sugar, just whatever dissolved impurities were floating about in it. I didn't see a single bubble or disturbance in it until I picked it up, at which point it sudenly and violently boiled over.

And Winona, you are totally nuts. Just not in this one case.

This is only vaguely related, but the microwaving water stuff reminded me of it...

Once when I was a kid I was bored and decided to play around with the temperature probe that came with our microwave, which we never used but I think it's for cooking meat. It was a metal, well, probe thing attached to a plastic coated wire that plugged into a jack inside the microwave. When plugged in and set to the right mode, the temp displayed where normally it shows the time.

Out of curiosity I put it in a bowl of ice to see if it would read below 32 degrees. When I turned it on, the part of the probe touching the ice started sparking, like what happens normally if you put metal in a microwave. I of course turned it off quickly and never tried that again.

I have no idea why the metal probe doesn't spark when used properly, so I don't know why lowering its temperature would cause that. Any guesses?

Most Canadians would be familiar with the "instant slush" phenomenon that occurs with beer that you forgot in the trunk of your car overnight (just ask Bob & Doug McKenzie, you hoser). I always assumed it had to do with pressure. Some of the bottles will have exploded, those that haven't erupt in a beer slushy as soon as you pop the cap.

I heard about the superheated water trick several years ago. It works best if you let a cup of water stand for half an hour or so. As someone mentioned it has something to do with there being no nucleation points for bubbles to form. After heating the water past the boiling point in your microwave you can them make it suddenly boil by doing anything that introduces some air; stir with a spoon, add some instant coffee, or even some cold water. That's the impressive bit - demonstrating how to make water boil by adding cold water!

I think I read somewhere that sometimes, in laboratories, small "nucleation stones" (like aquarium gravel) are sometimes put into liquids to ensure that they boil at their correct boiling point.

There are useful applications of this super-saturation and supercooling effect too. A compnay sells therapy pads for muscle pain that contain a supersaturated solution of some form of mineral salt and a piezoelectric "worm"; When cool, the fluid is clear and can be used as an ice pack. But when you bend the "worm" like a switch, thus causing a small electric charge to be produced, this triggers the salt to crystallise and go milky and solidify, and the process also gives off a large amount of heat for an hour or more, again useful for muscle aches. Putting the pad in the freezer reverts the solution again.

It's SCIENCE!! LOL

This behaviour of water is described in Jules Verne's "Hector Servadac" (little Nina(?) throws a rock into flat-calm sea causing it to instantly freeze).

Back when I was a college student, my roommate and I would notice this.

We had our mini fridge set to maximum cold. Because of room's sake, we usually store a couple bottles of Aquafina in the freezer.

Our first semester we noticed that if we shook the bottles after taking them out they'd freeze. No opening was involved, just grab and shake. Then bam, a MASSIVE core of ice taking up almost the entire volume of the bottle.

I'm kind of glad that showed it was LOW in impurities, as we were getting worried it had to do with some sort of contamination.

This makes a lot of sense when you apply it to nature. The way in which rain turns to snow is only partly due to temperature; There needs to be dust in the air for the snowflake crystals to form on as well, so if the air is too clear there is no snow, just sleet or hail.

This is absolutely true. I live in a place where it gets pretty cold at night (into the teens or single digits) and I have been known to leave unopened bottles of water in my truck. When you open one, it turns to slush in about a second. Fast, but slow enough to watch it go from bottom to top. I have done this intentionally on at least 20 occasions. My kids think it's cool. It doesn't work if you shake it, only if you open it. Therefore, it has to be the pressure change.

Our freezer does this to our bottled water all the time. I have been able to very slowly and without disturbing the water, open it and actually drink a bit of the super cold water, place the cap on it againt, then strike it against a table and it will turn to slush. So I don't think it is the pressure change. You don't even have to open the bottle, just strike it against a table and it will slush from the top down to the bottom in two or three seconds.

I've accidentaly stumbled upon this strange reaction of water (ice.. whatever) when trying to make some hot chocolate. I put the powder in a plastic cup and took out an unopened bottle of water out of my mini-fridge. As I poured, the water froze in the cup and the water that touched the ice froze, thus: as I poured, the ice seemed to rise towards the bottle. My room-mates thought I was doing a magic trick... Its not magic, its science!

I actually believe the supercooling effect has something to do with the shock of the molecules turning it completely frozen. i dont think it has anything to do with pressure, the shock disturbs the molecules causing it to turn into ice and then as a follow up a reaction affecting the entire bottle occurs.

It is a matter of pressure. As pressure increases boiling point goes up and freezing point goes down.

I just want to give props to the Cat's Cradle reference. Huzzah!

This is not a matter of pressure. This is a matter of impurities and crystalization. The opposite thing happens with super heated water. Shaking may not work but just a smaller disturbance would do to turn it to ice

sometimes the "superheating" occurs if you left the cup in the microwave after heating it, then you have to reheat it because it is cold. quite a lot of the impurities would have boiled away in the first heating, so it would be pretty pure. it would boil over once you added an impurity to it, like a cube of sugar. 15