Water; has unusual exotic features (Introduction)

by David Turell , Sunday, April 29, 2018, 21:04 (2399 days ago) @ David Turell

Water is necessary for life and its strange features look as if designed:

http://nautil.us//blog/why-water-is-weird?utm_source=Nautilus&utm_campaign=b5cbb05c...

"In their study published last month, Hajime Tanaka, John Russo, and Kenji Akahane—all researchers in the Department of Fundamental Engineering at the University of Tokyo, in Japan—tried to tease apart what makes water unique among liquids. It’s got anomalous properties, like expanding when cooled below 40 degrees Fahrenheit, which explains why lakes freeze downward, from top to bottom, rather than up. Normally frozen solids are more dense than their liquid equivalents, which would mean that frozen chunks would fall to the bottom of a lake instead of staying on top. Water also becomes less viscous compared to other liquids when compressed, and has an uncanny level of surface tension, allowing beings light enough, like insects, to walk or stand atop it. Since it’s these distinctive features among others that power our climate and ecosystems, water can appear to be “fine-tuned” for life.

“'With this procedure,” Russo said, “we have found that what makes water behave anomalously is the presence of a particular arrangement of the water’s molecules, such as the tetrahedral arrangement, where a water molecule is hydrogen-bonded to four molecules located on the vertices of a tetrahedron,” a shape of four triangular planes. “Four of such tetrahedral arrangements can organize themselves in such a way that they share a common water molecule at the center without overlapping,” Russo said. As a result, when water freezes, it creates an open structure, mostly empty space and less dense than the disordered structure of liquid water, which is why water props ice up. Both highly ordered and disordered tetrahedral arrangements give water its “peculiar properties.”

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"The ancient Greeks may have been wrong about water being an essential element, but Saykally says it’s no coincidence that water is essential for life on Earth. “It’s something intrinsic about water in that the strong tetrahedral hydrogen bond network that water makes is a very flexible environment for chemical processes to happen,” he said. “It has the right properties to dissolve many ions; it has the right properties to cause what we call hydrophobic materials”—like proteins—“to fold up in special ways.'”

Comment: Water is certainly part of the fine-tuning for life.