Recently, when making some sugar syrup, I found out about supersaturation, and looked at it's wikipedia article. I followed at link at the bottom of the article to another article, about supercooling. I tried it out, by getting a small bottled water bottle, and putting it into a freezer. It turned out to be true, when I opened the freezer it was still liquid, whacking it against the table started turning it to ice at the top, then gradually working it's way down. It was impressive, I recommend some people here do it for the sheer look of it. The wikipedia article is at http://en.wikipedia.org/wiki/Supercooling A web page about this which includes some interesting photos is at http://f0rked.com/articles/supercooling

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You should look into superheating as well. It's very interesting. And it's actually very dangerous for microwave oven user, which most manufacturer fail to indicated that boiling water using microwave oven is that harmful.

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



Quite similar to supercooling, but in opposite direction. I wonder if there's anymore other super_______ (fill in the blanks) exist? Maybe should change the title of this topic and add more info here .

 

 

 

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That's realy cool . I've seen some videos from people trying this out, realy worth the search (for those people who are too lazy to try it themself ).

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Here's a step by step of how I've done this:

If you're so inclined (and have the balls and spare dishes), get a dish that is perfectly smooth...that is, no facets, no hard lines...a wine glass works well for this, as do some other drink glasses. Basically, the simpler, the better. Make sure the glass is *spotless* also. You can't have anything that would form a nucleation site (which would cause the water to boil and release energy in a very less-than-dramatic fashion).

Put some water in it, about 3/4 full...and heat it for awhile. You should have a general idea how long it takes to boil water in your microwave, heat it about to that point. If you have an infrared thermometer just make sure the temperature is above 212F/100C.

For the fun part, take the water out of the microwave (carefully) and drop a coarse substance into the water. A teabag (how I found this little trick out -- the hard way, mind you) works pretty well, as does any non-soluble substance. Salt works ok, but it changes the boiling point of the water, sugar might work, but I haven't tried it. A penny will work fine too.

If the water is sufficiently superheated, the vessel containing it will explode on contact when it flash boils. Impressive effect.

Have fun

Oh yea, and wear eye protection and gloves or something.

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I saw a video of this on YouTube a few weeks ago. Most microwave manufacturers do tell you to not use the product for boiling water, in the "Important Safety Precautions" at the front of the manual. THey also tell you not to use the appliance for drying clothes, but that's another matter.

A couple of years ago a friend sent an email around telling people about what can happen when you boil water in microwave ovens. Guess it is true.

As for supercooling, can you give some more instructions on how to do it?

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Or drying cats either...poor kitteh

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Whoa, I've never seen anything like this before, thanks for sharing. I've watched a bunch of videos on youtube of people doing it and I really want to try this now lol.

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Well the thing is, the user of microwave oven don't always read the manual, OR worse, don't has access to the manual.

During a break of the part time class I took few years back, we would put a glass of water to heat it up in the microwave oven, then make a tea or milo. The lecturer thought us that, and no one ever mentioned about the danger of it. Luckily no incident has happen yet, since most of us only heated it for 1 min, just enough for a hot drink, but not long enough to reach 100C.

I do read that those microwave oven with rotating carrousel might have avoided susch problem, as the virbration will have started the boiling process, thus preventing superheating from happening.

Can anyone try it and let us know the result? But be careful

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Wow, that is cool…

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This is very impressive. I had a look at a few of the Youtube videos and I couldn't believe what was happening!!! The superheating is a little scary. I wasn't aware that you weren't supposed to boil water in the microwave, so I think I'll just stickto the good old kettle for boiling water.
I'm going to have to try some supercooling for myself, it just looks too fun

(edit)
This didn't seem to warrant it's own thread, but...
I was just looking at some of the Youtube vids from the this thread when I came across non-newtonian fluids.

From what I can understand about these things, they are a fluid, but the viscosity is altered depending on the amount of force being applied to the fluid. After reading a bit, I found that quicksand is a type of non-Newtonian.

Probably the most impressive example if these two guys, and their swimming pool full of non-Newtonian fluid


How about:

• Superfluid (not sure exactly, but looks like it reaches 0 viscosity)
• Supersolid (I think, reaches the same properties as a superfluid, but in a solid state at low temperatures ???)
• Superconducticity (cooling some materials to a point where they produce magnetic fields ???)
• Superdiamagnetism (loss of magnetic field at low temperatures, associated with superconductivity)

Cheers,
Hoopa

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