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Israeli Scientists Freeze Water By Warming It 165

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."
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Israeli Scientists Freeze Water By Warming It

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  • Re:I could be stupid (Score:5, Interesting)

    by SimonTheSoundMan ( 1012395 ) on Saturday February 06, 2010 @06:55AM (#31044542) Homepage

    I thought pure water doesn't go solid, not until an impurity starts crystal formation that turns the water into a solid?

  • Israeli Scientists (Score:5, Interesting)

    by Anonymous Coward on Saturday February 06, 2010 @07:02AM (#31044582)
    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?
  • by ls671 ( 1122017 ) * on Saturday February 06, 2010 @07:14AM (#31044628) Homepage

    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 ?

  • Re:I could be stupid (Score:4, Interesting)

    by ortholattice ( 175065 ) on Saturday February 06, 2010 @07:49AM (#31044758)

    You missed the point. The neat thing is that water was liquid, and then they WARMED it, and it froze. [...] they reversed the normal COLD-WARM SOLID-LIQUID order.

    In this supercooled water experiment [] video, notice that the supercooled water freezes after the bottle is tapped. So energy is put into it, meaning that it is warmed up slightly. Isn't this also reversing the cold-warm solid-liquid order?

  • by wisebabo ( 638845 ) on Saturday February 06, 2010 @07:49AM (#31044760) Journal

    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.

  • Re:Applications? (Score:4, Interesting)

    by kamochan ( 883582 ) on Saturday February 06, 2010 @08:53AM (#31044950)

    Apply that weird surface to generate the weird behaviour, and use it to power a Stirling engine.

  • Re:I could be stupid (Score:4, Interesting)

    by Devout_IPUite ( 1284636 ) on Saturday February 06, 2010 @09:27AM (#31045088)
    But it wasn't really a difference in the water, it was a difference in the container around the water. That is a well known phenomenon with airborn freezing temperature water, that it freezes on impact instead of while traveling through (clean) air.
  • Re:I could be stupid (Score:5, Interesting)

    by pj81381 ( 1703646 ) on Saturday February 06, 2010 @09:37AM (#31045130)

    I thought pure water doesn't go solid, not until an impurity starts crystal formation that turns the water into a solid?

    This comment seems really unintuitive so I looked around a little. Ice [] can actually form entirely without crystallization, by cooling it to ~137 C in a matter of milliseconds. The article also mentions that "pure water, in the absence of any nucleating surface, can remain in a supercooled liquid state down to temperatures as low as -40C". I guess that means that pure water will begin crystallizing at this temperature anyway.

  • by morgan_greywolf ( 835522 ) on Saturday February 06, 2010 @09:39AM (#31045134) Homepage Journal

    So first they cool it to -17 degree and it remains a liquid, then they warm it up to -7 degree and it freezes. That's like traveling from Greenwich to the Arctic via Antarctica and then call it a scientific discovery that one can actually reach the Arctic by going south, right?

    No, it's more like the realization that Canada is south of Detroit [].

  • by Jane Q. Public ( 1010737 ) on Saturday February 06, 2010 @10:43AM (#31045442)
    Actually, your typical Budweiser is roughly around 3.4% alcohol by volume, which is quite weak. In the days before and during Prohibition it would have been scoffed at and called "Near Beer", made for kids. But it is that way today because of post-Prohibition laws that restricted beer to lower alcohol levels. In some states that is. For some reason around 3.3-3.4% was a fairly common level when it came to such laws.

    My state used to have some weird laws carried over from those days. They have changed somewhat since. But until pretty recently, (1) it was illegal to show alcohol content on bottles, cans, or their packaging. (2) Beer bought in regular stores was limited to 3.4% alcohol by volume. But you could get beer or ale of higher alcohol content at a state liquor store.

    That led to some strange situations. For example, you could get Rainier Ale in the store, at 3.4%, and at the liquor store at about 9% if I remember. But because of the law, there was no indication of strength on the cans, which all had identical green and gold printing. So people made some pretty major mistakes now and then.

    Fortunately the laws here have become somewhat more reasonable, but a typical domestic mass-produced lager in most of the U.S. is still usually around 3.4%. It's getting better, though, with all the smaller breweries that have started up.
  • by Anonymous Coward on Saturday February 06, 2010 @11:26AM (#31045688)

    You could make one heck of a freeze gun with this technology... spray things and they freeze

  • by jschen ( 1249578 ) on Saturday February 06, 2010 @12:33PM (#31046092)
    Modded very funny, but with some element of truth. The grandest experiments in physics often require significant international collaborations and highly specialized instrumentation (think Large Hadron Collider) that demand large-scale pooling of resources. On the other hand, at least at this time, there really are no projects with such requirements in chemistry. Sure, there are many vibrant chemistry collaborations, but not nearly of that scope. So you can easily end up working only with people nearby, competing with a similarly capable team in another country (or in the same building). There are plenty of interesting problems in chemistry where a single person or a small group could produce a significant breakthrough through the creative design and execution of simple experiments using readily available equipment and chemicals.
  • by Pictish Prince ( 988570 ) <> on Saturday February 06, 2010 @02:28PM (#31046912) Journal

    Not only is it not particularly hoppy, it has a pretty significant rice content. If anything, bud is hop-flavored rice alcohol. This being said, it's still my favorite mass market beer.

    Yes, we live in a cultural backwater as far as beer is concerned. In Mexico the cheap regular beer is some of the best on the planet.

  • Re:I could be stupid (Score:3, Interesting)

    by Lehk228 ( 705449 ) on Saturday February 06, 2010 @08:09PM (#31049048) Journal
    you can replicate it yourself, leave a water bottle out in the garage when it's about 20 F out. take it inside and smack it against your hand, if the temperature is right you can watch the ice form. it works even better with non-carbonated flavored waters.

The other line moves faster.