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Israeli Scientists Freeze Water By Warming It

Posted by timothy on from the you-must-become-the-frozen-water dept.

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."

27 of 165 comments (clear)

  1. I could be stupid by PakProtector · · Score: 4, Insightful

    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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    1. Re:I could be stupid by SimonTheSoundMan · · Score: 5, Interesting

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

    2. Re:I could be stupid by Trepidity · · Score: 5, Informative

      Salt and anti-freeze just have typical freezing-point depression; there's no way to use them to produce a situation where water that is a stable liquid at one temperature will turn solid if you increase the temperature. The situation in this experiment is that water that's liquid at -17 C will freeze as you head it up towards -7 C.

      --
      10 PRINT CHR$(205.5+RND(1)); : GOTO 10
    3. Re:I could be stupid by Ardeaem · · Score: 4, Informative

      You missed the point. The neat thing is that water was liquid, and then they WARMED it, and it froze. It is just a gimmick, but it's not just that they managed to get it to freeze at a temperature below 0C. It's that, due to the interaction between temperature, charge, and the freezing point, they reversed the normal COLD-WARM SOLID-LIQUID order.

    4. Re:I could be stupid by ortholattice · · Score: 3, Interesting

      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?

    5. Re:I could be stupid by Linzer · · Score: 5, Informative

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

      In many cases, the surface of the container has defects which can play that role.

      --
      Gravitation is a theory, not a fact.
    6. Re:I could be stupid by Devout_IPUite · · Score: 3, Interesting

      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.

    7. Re:I could be stupid by pj81381 · · Score: 5, Interesting

      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.

    8. Re:I could be stupid by Gibbs-Duhem · · Score: 5, Insightful

      Exactly, this is well known, and is the difference between homogeneous nucleation caused by the massive undercooling providing the energy to nucleate ice spontaneously versus heterogeneous nucleation which requires much less free energy and occurs dependent on surfaces.

      It is not scientifically interesting that they warmed it to get it to freeze, that's just a comparison of freezing points... it's interesting that the charge of the surface modified the freezing/nucleation point. Frankly, I am amazed that this was published in Science; it seems like worthwhile research, but for a journal more like, say... applied physics letters or a more specific interest journal. Kudos to the researchers for managing to spin it as a general-interest paper when it is in fact a fairly simple observation of an obscure phenomena.

  2. Applications? by paskie · · Score: 3

    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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    1. Re:Applications? by kamochan · · Score: 3, Interesting

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

    2. Re:Applications? by PopeRatzo · · Score: 5, Funny

      but are there some cool real-world applications I'm not thinking of?

      A pyroelectric lithium tantalate ice cube tray? In animal shapes?

      --
      You are welcome on my lawn.
    3. Re:Applications? by aBaldrich · · Score: 3, Insightful

      They are scientists, not engineers.

      --
      In soviet russia the government regulates the companies.
  3. Progress by brettz9 · · Score: 5, Funny

    It's not quite Hell, but it's an impressive step in that direction...

  4. Overflow by Anonymous Coward · · Score: 3, Funny

    By reading the title only, I thought the overflow-bug of water was finally found.

  5. Israeli Scientists by Anonymous Coward · · Score: 5, Interesting

    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?

    1. Re:Israeli Scientists by Spad · · Score: 5, Funny

      Obviously Chemists are more nationalistic than Physicists...

    2. Re:Israeli Scientists by Trepidity · · Score: 5, Informative

      Slashdot headlines seem to do it now and then:

      Canadian Scientists Regrow Teeth

      French Scientists Link Higher BMI with Lower IQ

      British Scientists Reverse Casimir Effect

      German Physicists Claim Speed of Light Broken

      Japanese Scientists Claim To Reconstruct Images From Brain Data

      Italian Scientists Put Robot Spiders In Your Colon

      etc.

      --
      10 PRINT CHR$(205.5+RND(1)); : GOTO 10
    3. Re:Israeli Scientists by Anonymous Coward · · Score: 3, Funny

      Wait until you see tommorow's story: American Slashdot Editors Add Superfluous Words When The Title is too Small.

  6. Nothing new I have noticed this with my beer ;-)) by ls671 · · Score: 4, Interesting

    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.
  7. Re:Nothing new I have noticed this with my beer ;- by spydum · · Score: 3, Informative

    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.

  8. That's nothing. by Timosch · · Score: 5, Funny

    One of these guys managed to turn water into wine 2000 years ago...

  9. Ah, I see you are an american by SmallFurryCreature · · Score: 5, Funny

    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.

    --

    MMO Quests are like orgasms:

    You may solo them, I prefer them in a group.

  10. Re:Dowsing by Smallpond · · Score: 4, Funny

    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."

  11. Re:Let me get this straight by morgan_greywolf · · Score: 3, Interesting

    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.

    --
    My blog
  12. Re:Contrary to what kids think by realityimpaired · · Score: 3, Informative

    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.)

  13. Whut? by Quiet_Desperation · · Score: 3, Insightful

    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.