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Israeli Scientists Freeze Water By Warming It
ccktech writes "As reported by NPR and Chemistry world, the journal Science has a paper by David Ehre, Etay Lavert, Meir Lahav, and Igor Lubomirsky [note: abstract online; payment required to read the full paper] of Israel's Weizmann Institute, who have figured out a way to freeze pure water by warming it up. The trick is that pure water has different freezing points depending on the electrical charge of the surface it resides on. They found out that a negatively charged surface causes water to freeze at a lower temperature than a positively charged surface. By putting water on the pyroelectric material Lithium Tantalate, which has a negative charge when cooler but a positive change when warmer; water would remain a liquid down to -17 degrees C., and then freeze when the substrate and water were warmed up and the charge changed to positive, where water freezes at -7 degrees C."
But I was expecting something along the lines of "Researchers manage to make water freeze at greater than 0C," instead of "Researchers manage to make water freeze below normal freezing temperature."
Haven't they ever heard of salt? Or Anti-freeze?
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"Qua!?"
That does sound really cool, even as a fundamental research, but are there some cool real-world applications I'm not thinking of?
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It's not quite Hell, but it's an impressive step in that direction...
By reading the title only, I thought the overflow-bug of water was finally found.
I don't remember the science story yesterday Physicists Discover How To Teleport Energy being called Japanese Physicists Discover How To Teleport Energy. Is the fact these scientists are Israeli title worthy?
When I put a beer in the freezer too long but not that long, when I take it out of the freezer, I can see it is pretty 100% liquid inside the bottle. Now, taking it out of the freezer makes it warmer and opening it even warmer due to air circulation inside the bottle.
Well, when I open it, it turns to ice so I make my beer freeze by making it warmer so nothing new here ;--))))
Very seriously, I swear this is true but I understand it could be due to other factors that the ones described in TFA like pressure inside the bottle but I thought it would interesting to mention anyway.
Haven't anybody else seen their beer freeze in their hand while opening it just after it has been in the freezer although it was in a liquid state when they actually took it out of the freezer ?
Everything I write is lies, read between the lines.
That's an old bar trick. It has to do with the co2 being released on pressure change. Nothing like the science these folks have described.
One of these guys managed to turn water into wine 2000 years ago...
You clearly must be an American, since you compare beer to water. Over here in the old world, we know there is a difference by the taste for one.
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He must be negatively charged (thus keeping water a liquid on or in him) and then the moment he "releases" it, it freezes!
Could there be some sort of industrial application for this, like ice-making where you have a jet of "liquid" water (because it is kept in a negatively charged apparatus) but upon contact with something, loses its charge and freezes? How about rapid construction of ice sculptures? Just like spray on concrete.
I even seem to remember someone in WWII proposing making giant pontoons/floating islands out of ice and hay.
How about in Antarctica/on Mars using it for rapid construction of ice domes? Once it solidifies it won't melt.
A dowser was working Down Under
when his failure caused him to ponder
"the charge on me watta
was more than it oughta.
So I couldn't tell lightning from thunder."
No, it's more like the realization that Canada is south of Detroit.
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I think he was referring to the fact that it tastes like fizzy water with beer-like flavour, not the alcohol content. And Budweiser tastes pretty darned watery, even compared against other beers of the same type. Ales usually have a heavier taste to them, so it's not really fair to compare Budweiser against something like Guiness or Caledonian in terms of flavour. It is, however, fair to compare it against a good lager like Pilsner Urquell. Even when you compare it against a shitty lager, like Labatt Blue (which is also a pilsner, like Budweiser), Budweiser comes out on the bottom.
(and no, I'm not saying that Canadian beer sucks, just that some of the most popular Canadian beers suck. Namely, Labatt and Molson. If you want a good Canadian beer, try something like Steam Whistle, or Wellington. We don't export the good stuff. Similarly, I think the Australians are smart enough to export the shitty beers and keep the good stuff for themselves, as are the Dutch... think about that when you order a Fosters or a Heineken.)
Hmm, water ice that is stable at a higher temperature than liquid water? Can anyone say ice-9?
Tantalum is non-toxic, but you know it doesn't really work like that. Sodium is explosive; chlorine is toxic; sodium chloride is tasty.
Still, as you say, lithium tantalate is going to be far too expensive for coating pipes.
It sounds like it freezes due to the change in charge, not because the water warms up. It's freezing in *spite* of the water warming. It's like they are just chasing the freezing point around.
You get the same effect when opening a highly chilled bottle of soda. It starts to freeze due to the release of carbonation, although the pressure change might come into play as well.
When you open it COs is released this causes the pressure to fall.
pV = nRT
So you did in fact cool it by opening it.
You could also supercool it I guess and shaking it a little when taking it out causes it to crystallize - but I'm having doubts about beer and beer bottles being pure enough to not crystallize out in the first place.
Water needs to reach the correct temperature and then have something trigger the phase transition.
In other words:
The crystallization has to start somewhere. Imperfections in the surface or impurities supply this. If you have very pure water and a "perfect" container, the lack of a starting point for crystallization can delay the phase transition by quite a bit.
(Then you get YouTube videos showing flash freezing of water bottles!/i))