* Astronomy

Water Doesn't Have to Freeze until -55 F

University of Utah chemists may have solved one enigma by showing how cold water can get before it absolutely must freeze: 55 degrees below zero Fahrenheit.
That's 87 degrees Fahrenheit colder than what most people consider the freezing point of water, namely, 32 F.
Supercooled liquid water must become ice at minus 55 F (-48°C) not just because of the extreme cold, but because the molecular structure of water changes physically to form tetrahedron shapes, with each water molecule loosely bonded to four others, according to the new study by chemists Valeria Molinero and Emily Moore.
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Weird world of water gets a little weirder

Strange, stranger, strangest! To the weird nature of one of the simplest chemical compounds - the stuff so familiar that even non-scientists know its chemical formula - add another odd twist. Scientists are reporting that good old H2O, when chilled below the freezing point, can shift into a new type of liquid. The report appears in ACS' Journal of Physical Chemistry B.
Pradeep Kumar and H. Eugene Stanley explain that water is one weird substance, exhibiting more than 80 unusual properties, by one count, including some that scientists still struggle to understand. For example, water can exist in all three states of matter (solid, liquid,gas) at the same time. And the forces at its surface enable insects to walk on water and water to rise up from the roots into the leaves of trees and other plants. In another strange turn, scientists have proposed that water can go from being one type of liquid into another in a so-called "liquid-liquid" phase transition, but it is impossible to test this with today's laboratory equipment because these things happen so fast. That's why Kumar and Stanley used computer simulations to check it out.
They found that when they chilled liquid water in their simulation, its propensity to conduct heat decreases, as expected for an ordinary liquid. But, when they lowered the temperature to about 54 degrees below zero Fahrenheit, the liquid water started to conduct heat even better in the simulation.
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Electric ice may pervade space. This strange form of water is more persistent than was previously thought, and the discovery could change our understanding of how the solar system formed. It might even give ice a new role in the emergence of the complex organic molecules needed for life.
In a single molecule of water - H2O - there is a charge separation. That's because the two positively charged hydrogen atoms cluster at one end, away from the single negatively charged oxygen.
However, the charges get mixed up when ordinary ice, known as ice Ih, forms. While the oxygen atoms arrange themselves in a repeating pattern, the pairs of hydrogen atoms that extend from them don't. Instead, they randomly take one of a number of positions
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