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With a little help, water can freeze as it heats up

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iceThe Celsius scale is an elegant, simple system of measurement: water freezes at 0 degree Celsius and boils at 100 degrees C. (The actual definition of the scale is a bit more complex, involving the so-called triple point of water, but that’s the general idea.) But chefs at high altitudes know that the simplicity of Celsius doesn’t always hold—the higher your kitchen, the lower the boiling point of water. Similarly, water’s freezing point is negotiable, with "supercooled" water able to remain liquid down to around –40 degrees, and even colder at extreme pressures. Supercooling can occur if water is so pure and is kept in such uncontaminated conditions that the molecules have nothing to interact with and crystallize around.

It has long been known that electrically charged surfaces can affect supercooled water’s ability to freeze, a fact unsurprising given that water is a polar molecule whose orientation and hence ability to crystallize can be controlled by electric fields. A study in the February 5 issue of Science explores the interaction between electric fields and supercooled water’s freezing point, even producing the counterintuitive phenomenon of water freezing as its temperature increases. The researchers, from the Weizmann Institute of Science in Rehovot, Israel, experimented with supercooled water on pyroelectric surfaces, materials that develop transient electric charges during temperature changes, either positive or negative depending on whether the pyroelectric is heated or cooled.

By using opposite sides of the same pyroelectric lithium tantalate crystal, the Weizmann team produced two surfaces with opposite charges during cooling—one surface developed a positive charge as the temperature decreased, the other a negative charge.

On an uncharged lithium tantalate surface, the water remained a supercooled liquid down to –12.5 degrees C. But when the pyroelectric surface had a positive charge, the team found that water froze at –7 degrees C; the positive charge somehow promoted the ice-forming process. Conversely, when the surface was negatively charged, the water did not freeze until –18 degrees C.

Even after the negative charge had worn off, the water remained in supercooled liquid form. But when the pyroelectric was heated from –11 degrees to –8 degrees C, thereby generating a positive charge on the surface, the water coalesced into a solid—freezing even as its temperature increased.

Ice photo: © iStockphoto/Milous

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  1. 1. Wayne Williamson 3:04 pm 02/7/2010

    This is such a cool article….Thanks…..

    Link to this
  2. 2. Ironman66 1:18 am 02/9/2010

    It is great that we have learned to manipulate the energy field of matter by changing the speed of the wave through the speed of the waves frequency and mode. this could benefit us in the medical field if properly applied to the human energy field.
    I would like to know who forgot the 6 state of matter,Tissue being that it is what intelligent life is made of?
    Tissue = the combination of solid and plasma states of matter

    Link to this
  3. 3. gates.steve143@gmail.com 11:00 pm 02/26/2010

    The day when i saw the information on particular Can water help? on http://www.weightlossguide.com i became a fan of this site.

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  4. 4. Ironman 12:06 am 02/27/2010

    Water boils at a lower temperature at altitude, Due to the atmosphere, and the electromagnetic energy field of the earth being less dense. The further away from sea level we get, the weaker the earths magnetic field is, as well as less atmosphere gasses & air , thus having less resistance for electrons protons to travel through. This allowing waves of energy ( excited electrons and protons or Heat in this case), to move faster with less resistance, allowing the water to boil at a lower temperatures, relevant to the (electrons/protons) speed of orbit around the mass of water being boiled..
    Have a great day, and enjoy the beauty of life’s journey.. =o)
    Bret Varcados

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  5. 5. Ironman 12:10 am 02/27/2010

    that was 7th state of matter liquid, gas, solid, plasma, TISSUE, Bose Einstein and fermionic condensate. Tissue = plasma and solid
    Have a great day and enjoy the journey of life.. =o)
    BV

    Link to this
  6. 6. Ironman 12:14 am 02/27/2010

    for a information on the reality and truth of the universe,
    How things work check out this blog.

    http://iparte.com/forum_view.php?forum_id=58

    Have a great day and enjoy the beauty of your journey.. =o)
    BV

    Link to this
  7. 7. LFCRedLV 2:14 pm 08/9/2010

    Hmmm… map the electromagnetic field on the surface of Mars and where you have the biggest negative charge, there’s your liquid water? Maybe in a shadowy canyon pool somewhere near the equator?

    Link to this

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