Scientists are arguing about two new types of water, and we don't mean Dasani or Perrier - we're talking about entirely new phases like "liquid" and "solid." Which proves that researchers get to fight about far better things than regular humans.
Simulations show two new types of supercooled water existing below minus seventy five degrees Celsius (around two hundred Velvin), and if you just pointed out that water freezes before that then you aren't quite the smartass as you think you are. Changing the pressure can change the phase transition points of water (for example, boiling water can be safely drunk at the top of Mount Everest), and applying large pressures to water can prevent it freezing - and perhaps lead to something else.
The key is the hydrogen bonds of water: H20 contains two hydrogen atoms, which we sincerely hope isn't news to you, but the hydrogen atoms are also attracted to oxygen atoms of other molecules - leading to a constant creation and destruction of weak hydrogen bonds between the molecules in a liquid (it's also this weak attraction that causes DNA to twist around itself in a helical shape!) Under extreme conditions, simulations show these hydrogen bonds radically rearranging: either in an open network, creating a Low Density Liquid, or sacrificing some of themselves to crush the water molecules together closer, creating a High Density Liquid.
Now a team of Indian and Italian scientists say they've seen the supercool fluids. The problem is that it's extremely hard to make water change this way and still get in to look at it. In these experiments, the researchers tagged the liquid with an organic probe molecule - so they can't actually see the water (as it's in a tiny region crushed between super-cold crystals of ice) but the probe. Their analysis of the probe's motion matches predictions of the new fluids' properties, but not everyone is convinced. Some say there may be a smooth transition rather than two distinct states, while others claim the odd observations are due to impurities instead of supercooled states.
It's an active area of discussion, but more important, the fact that this is water should be an important reminder for you: there is amazing new science in places you'd never expect.
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