Water; required for life

It is a very strange substance, two gases make a liquid that can take many forms. Its strangeness explored:-http://nautil.us/issue/25/water/five-things-we-still-dont-know-about-water-"1) How Many Kinds of Ice Are There?-"At latest count, there are 17 different crystalline forms of solid water. However, only one formIce Ihexists commonly on Earth outside of the laboratory. A second crystalline form called Ice Ic is present in very minor amounts in the upper atmosphere, and another 15 forms occur only at very high pressures. (There is also a lot of water in interstellar space, but it is usually an amorphous, non-crystalline, glassy ice frozen onto dust grains.)-"The remarkable variety of crystalline ice forms results from the tetrahedral network of strong hydrogen bonds formed among neighboring water molecules. In the condensed phases of water, each molecule optimizes its hydrogen bonding capacity by forming four hydrogen bonds at near-tetrahedral angles. The hydrogen bonds inside Ice Ih form an open, three-dimensional structure with a low density.-"2) Are There Two Kinds of Liquid Water?-"3) How Does Water Evaporate?-"4) Is the Surface of Liquid Water Acidic or Basic?-"5) Is Nanoconfined Water Different?"-Read more to find out

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Another study of water's unique properties as a requirement for life:-http://phys.org/news/2016-01-uncover-unusual-properties.html-
"In many ways, water behaves very differently than other liquids do, and with important consequences: It's widely thought that water's unusual properties were essential for the development of life on Earth. One prime example is the fact that ice floats. Unlike other substances, frozen water is less dense than liquid water, and this anomaly allows fish and other aquatic lifeforms to survive in the water under a frozen layer of protective ice during cold periods. Water also has a high heat capacity, meaning it can absorb and release a large amount of heat while undergoing very little change in temperature. This property helps many living organisms maintain a relatively stable body temperature, and it also provides a pleasant climate in Europe due to the warm Gulf Stream current. 
 
"It's widely known that water's anomalous properties are related to its hydrogen bonds, which cause liquid water to arrange itself in a highly ordered way because of the attraction between the hydrogen atoms in one water molecule and the oxygen atoms in adjacent molecules. However, researchers do not completely understand how water's unique hydrogen-bonded structure leads to its anomalous properties. -***-"It is the fluctuations between high-density liquid and low-density liquid that give rise to the anomalous properties," Nilsson told Phys.org.-"Take water's large heat capacity, for instance. As Nilsson explained, heat capacity is related to entropy fluctuations, and entropy is in turn related to the number of possible ways the available energy can be distributed in the system. Fluctuations between the low- and high-density local structures increase the magnitude of the entropy fluctuations and, consequently, the heat capacity.-***-"While the new paper combines many years of data into one cohesive picture, many questions still remain. One unanswered question, for instance, is why does water's anomalous region occur at the same temperatures and pressures that sustain life? It seems likely that water's anomalous region served to place constraints on the conditions required for life to exist. A better understanding of this overlap could have implications for understanding life on a fundamental level."
(my bold)-Comment: I view water's unique properties as part of the fine tuning of this universe to allow life to appear. Our bodies are about 90% water so the reasoning fits.

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Water has many strange properties still being studied and understood:

http://phys.org/news/2016-12-uncovering-secrets-ice-materials.html

"Water is vital to life on Earth and its importance simply can't be overstated—it's also deeply rooted within our conscience that there's something extremely special about it. Yet, from a scientific point of view, much remains unknown about water and its many solid phases, which display a plethora of unusual properties and so-called anomalies that, while central to water's chemical and biological importance, are often viewed as controversial.

***

"Whenever liquid water freezes, only its oxygen atoms actually end up in fixed positions," explained Christoph G. Salzmann, associate professor and Royal Society Research Fellow, Department of Chemistry, University College London. "The hydrogen atoms remain disordered—so we call such phases of ice 'hydrogen disordered.' Upon cooling, the hydrogen atoms are expected to become ordered and result in hydrogen-ordered ices. Yet, this process is difficult because the reorientations of the hydrogen-bonded water molecules are highly cooperative."

"To help explain the concept, he used a tile game as an analogy.
"Moving from disorder to order is difficult work because the tiles can't move independently—similar to the situation in ice," he said.

***

"Ice VI and ice XV are both high-pressure phases of ice that form at about 10,000 atmospheres. "The structure of ice XV has been the topic of lively scientific discussion for years," Salzmann said. "A variety of different and, in part, conflicting models have been suggested from both experimental data—including a previous study by our group—as well as computational studies."

***

"The group's work represents a major change in the understanding of ice XV that consolidates much of their previous work. "First, we've shown using neutron diffraction at the ISIS Science and Technology Facilities Council in the U.K. that the ice shrinks in two directions, but expands in the third during the transition from ice VI to XV," he explained. "Using density functional theory calculations, we can show that only one particular structural model of ice XV is consistent with these changes."

"Incidentally, this structure is also the one the group proposed from their in-depth analysis of neutron data.

"'This agreement between experiment and calculations is great, in particular, because there have been conflicting views regarding ice XV," he added. "The overall volume of the ice increases during the phase transition, which finally explains why the transition is observed more readily at ambient pressure than at higher pressures—behavior that has puzzled us for a long time."

***

"'There's still an open question about why we can't achieve full order in ice XV," Salzmann said. "We've already started new experimental work to explore how the properties of ice change within nanoconfinements and the presence of chemical species—because we're interested in understanding the complex behavior of ice on comets and within our atmosphere.'"

Comment: Water in general has weird properties. When water freezes the ice expands to a larger volume and floats. This helps aquatic animals and plants to stay under it in liquid water and remain protected from the colder environment above the ice. Is this a part of the fine tuning for life. As we understand more about the properties of water on comets we may find more evidence of fine tuning.

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More weird properties for water:

https://www.livescience.com/59612-liquid-water-exists-in-two-forms.html?utm_source=ls-n...

Liquid water comes in two forms — low density and high density, scientists have found.

" The findings add to the anomalous properties of this ubiquitous, life-giving liquid, which is like no other on Earth.

"'The new remarkable property is that we find that water can exist as two different liquids at low temperatures where ice crystallization is slow," Anders Nilsson, a chemical physicist at Stockholm University in Sweden, said in a statement.

"It turns out that water has strange physical properties found in no other liquids known to scientists. For one, it can exist in all three phases at Earth-like temperatures and pressures. For another, its molecular configuration — two hydrogens mated to an oxygen molecule — creates strong polarity, or a highly positively charged region and a highly negatively charged region. That, in turn, allows almost any substance to be dissolved in it; in that way, substances such as calcium ions can travel (dissolved) within water into and out of a cell, for instance.

***

"Researchers have long known that ice can exist in two solid forms: a highly ordered, crystalline form with individual molecules neatly lined up in a repeating pattern, and an amorphous version, where the molecules are scattered more haphazardly. In fact, this amorphous ice is the most abundant type on our planet, and can transform between both a low- and high-density version.

"Scientists wondered whether a similar transition may occur in liquid water. To find out, Nilsson and his colleagues used X-rays to track the distance between individual molecules of H20 at low temperatures. Using this technique, they watched as the water transitioned from an amorphous, glassy, frozen liquid state (essentially, uncrystallized ice), to a viscous liquid, and then almost immediately to another, more viscous liquid with a lower density, the researchers reported today

"The findings shed new light on the bizarre behavior of liquid water.

"'The new results give very strong support to a picture where water at room temperature can't decide in which of the two forms it should be, high or low density, which results in local fluctuations between the two," study co-author Lars G.M. Pettersson, a theoretical chemical physicist at Stockholm University, said in the statement. "In a nutshell: Water is not a complicated liquid, but two simple liquids with a complicated relationship.'"

Comment: Water is a strange substance, a liquid as the result of two gases combining, and it allows solutes like calcium o travel through cell walls. It is one of the fine tuning aspects of this universe.

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Under high pressure and heat it fits a theory about Neptune and Uranus water:

https://www.nytimes.com/2018/02/05/science/superionic-water-neptune-uranus.html?rref=co...

"Scientists have confirmed a form of water that is simultaneously solid and liquid. It is the latest advance in the study of water, a seemingly simple substance that can shift between many different configurations.

“'That’s a really strange state of matter,” said Marius Millot, a physicist at Lawrence Livermore National Laboratory in California, the lead author of a paper published Monday in the journal Nature Physics that describes the experiments.

"This new form, called superionic water, consists of a rigid lattice of oxygen atoms through which positively charged hydrogen nuclei move. It is not known to exist naturally anywhere on Earth, but it may be bountiful farther out in the solar system, including in the mantles of Uranus and Neptune.

***

"When squeezed, the hydrogens and oxygens shuffle into other crystal structures; scientists now know of more than a dozen different forms of ice.

"Theorists first suggested 30 years ago that superionic water might exist under extremely high pressures and hot temperatures. The heat melts the chemical bonds between the hydrogen and oxygen atoms. The high pressure keeps the larger and heavier oxygen atoms stacked in a fixed crystal alignment — a solid — while the hydrogen nuclei, or ions, flow through — a liquid.

"That makes it a conductor of electricity like a metal, but the current is carried by positively charged ions instead of negatively charged electrons.

***

"In the new experiment, scientists at Lawrence Livermore first squeezed water between two pieces of diamond with a pressure of 360,000 pounds per square inch. That is about 25,000 times greater than the air pressing against you here on the surface of Earth, and the water is squeezed into a type of ice known as ice VII, which is about 60 percent denser than usual water, and solid at room temperature. Each diamond cell contained about one-seven-millionth of an ounce of water.

"The researchers then took the compressed ice, packed in carry-on luggage, to the University of Rochester where it was blasted by a pulse of laser light. That caused shock waves through the ice that lasted 10 to 20 billionths of a second, heating it to thousands of degrees and exerting a pressure more than a million times that of Earth’s atmosphere. Those conditions exist inside Uranus and Neptune and undoubtedly within numerous ice giants around other stars.

***

"Here, Dr. Millot and his colleagues were able to capture the optical appearance of the ice. If electrons were moving around, it would have been reflective. (That is why metals are shiny.) Instead, the sample was opaque. That pointed to the movement of ions instead, indicating a superionic ice.

"The superionic ice melted into a liquid at about 8,500 degrees Fahrenheit.
“It is a rather amazing experiment and the results are consistent” with theoretical and computational predictions, said Roberto Car, a chemistry professor at Princeton.

"The superionic ice could help explain the lopsided, off-center magnetic fields of Uranus and Neptune, the solar system’s seventh and eighth planets that are known as ice giants and were visited briefly by NASA’s Voyager 2 spacecraft in the 1980s. Instead of Earth’s magnetic field generated at the core of the planet, the fields of those icy bodies may originate, in part, within shells of superionic ice inside their mantles."

Comment: Water is a strange vital component of the Universe with many very unexpected forms.

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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.”

***

"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.

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Another study shows water molecules come in to types:

https://www.sciencedaily.com/releases/2018/05/180529092134.htm

"Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities.

"From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two different forms (isomers) at the molecular level. The difference lies in the relative orientation of the nuclear spins of the two hydrogen atoms. Depending on whether the spins are aligned in the same or opposite direction, one refers to ortho- or para-water.

***

"It was demonstrated that para-water reacts about 25% faster than ortho-water. This effect can be explained in terms of the nuclear spin also influencing the rotation of the water molecules. As a result, different attractive forces act between the reaction partners. Para-water is able to attract its reaction partner more strongly than the ortho-form, which leads to an increased chemical reactivity. Computer simulations confirmed these experimental findings.

"In their experiments, the researchers worked with molecules at very low temperatures close to the absolute zero point (about -273°C). These are ideal conditions to precisely prepare individual quantum states and define the energy content of the molecules, and to cause a controlled reaction between them. Willitsch explains the experimental approach: "The better one can control the states of the molecules involved in a chemical reaction, the better the underlying mechanisms and dynamics of a reaction can be investigated and understood.'"

Comment: It is strange that two gases end up as a very versatile liquid which makes life possible. Looks designed to me.

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Hot, very heavy black superionic water is found under laser pressure; type XVIII:

https://www.quantamagazine.org/black-hot-superionic-ice-may-be-natures-most-common-form...

"The discovery of superionic ice potentially solves the puzzle of what giant icy planets like Uranus and Neptune are made of. They’re now thought to have gaseous, mixed-chemical outer shells, a liquid layer of ionized water below that, a solid layer of superionic ice comprising the bulk of their interiors, and rocky centers.

"Recently at the Laboratory for Laser Energetics in Brighton, New York, one of the world’s most powerful lasers blasted a droplet of water, creating a shock wave that raised the water’s pressure to millions of atmospheres and its temperature to thousands of degrees. X-rays that beamed through the droplet in the same fraction of a second offered humanity’s first glimpse of water under those extreme conditions.

"The X-rays revealed that the water inside the shock wave didn’t become a superheated liquid or gas. Paradoxically — but just as physicists squinting at screens in an adjacent room had expected — the atoms froze solid, forming crystalline ice.

***

"The findings, published today in Nature, confirm the existence of “superionic ice,” a new phase of water with bizarre properties. Unlike the familiar ice found in your freezer or at the north pole, superionic ice is black and hot.

***

"Across the solar system, at least, more water probably exists as superionic ice — filling the interiors of Uranus and Neptune — than in any other phase, including the liquid form sloshing in oceans on Earth, Europa and Enceladus. The discovery of superionic ice potentially solves decades-old puzzles about the composition of these “ice giant” worlds.

"Including the hexagonal arrangement of water molecules found in common ice, known as “ice Ih,” scientists had already discovered a bewildering 18 architectures of ice crystal. After ice I, which comes in two forms, Ih and Ic, the rest are numbered II through XVII in order of their discovery. (Yes, there is an Ice IX, but it exists only under contrived conditions, unlike the fictional doomsday substance in Kurt Vonnegut’s novel Cat’s Cradle.)

"Superionic ice can now claim the mantle of Ice XVIII. It’s a new crystal, but with a twist. All the previously known water ices are made of intact water molecules, each with one oxygen atom linked to two hydrogens. But superionic ice, the new measurements confirm, isn’t like that. It exists in a sort of surrealist limbo, part solid, part liquid. Individual water molecules break apart. The oxygen atoms form a cubic lattice, but the hydrogen atoms spill free, flowing like a liquid through the rigid cage of oxygens.

***

"Depending on whom you ask, superionic ice is either another addition to water’s already cluttered array of avatars or something even stranger. Because its water molecules break apart, said the physicist Livia Bove of France’s National Center for Scientific Research and Pierre and Marie Curie University, it’s not quite a new phase of water. “It’s really a new state of matter,” she said, “which is rather spectacular.”

***

"The new analyses also hint that although superionic ice does conduct some electricity, it’s a mushy solid. It would flow over time, but not truly churn. Inside Uranus and Neptune, then, fluid layers might stop about 8,000 kilometers down into the planet, where an enormous mantle of sluggish, superionic ice like Millot’s team produced begins. That would limit most dynamo action to shallower depths, accounting for the planets’ unusual fields."

Comment : Weirder than ever. Water, necessary for life and all over the place in the universe in strange forms. On purpose?

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Another review of water's many properties:

https://inference-review.com/letter/unresolved-anomalies

"Water’s uniqueness is apparent in its pressure-temperature phase diagram, which, particularly in the low temperature region, is not only complicated, but also contains several ice phases. Most boundaries between the ice phases, and particularly those in the liquid phase, are parallel to the temperature axis, reflecting density-driven phase changes. There are also entropy-driven transitions, with phase boundaries parallel to the pressure axis. Marc Henry’s essay on the properties of supercooled water offers an intriguing top-level argument about one of the most fascinating behaviors of H2O.

"Despite being essential for daily life, water remains mysterious, exhibiting almost 40 anomalous properties. A partial list of its unexpected behaviors includes a high boiling point and surface tension; a high enthalpy of fusion—almost 41 kJ/mol, compared to 19 kJ/mol for H2S—which significantly lowers the cryoscopic constant; a maximum density at 3.98°C; a high melting point due to its low entropy in the liquid state; a lower melting point as pressure increases, and hence a negative value in the slope of the ∂P/∂T curve in the phase diagram, until about –22°C at 210 MPa; 9% volume contraction during melting, similar to other tetrahedral solids such as Si or SiO2; high viscosity and Arrhenius activation energy of the viscous flow; anomalous changes in its viscosity upon cooling, in high temperatures, and at high pressure; a low value of isothermal compressibility, and of isobaric expansion, high isobaric heat capacity in the liquid state, which drops 50% in the solid and vapor states; more neighbors in the liquid state with increasing temperature; a minimum in the solubility of gases and of scarcely soluble materials as temperature increases; and a large dielectric constant.

"Some of these anomalies are responsible for remarkable natural phenomena: icebergs float, energy from the sun is redistributed across the oceans and between the oceans and the atmosphere, capillary forces allow trees to lift enormous amounts of water to their leaves, climates in humid areas remain moderate, and natural convection occurs in water basins.

***

"More than 400 years later, a topic in this debate—the structure of liquid water—is still vigorously discussed. Investigations into short- versus long-range water structure have spawned a multitude of published studies. The existence of high-density versus low-density water has been invoked. Hydrogen-bond clusters in expanded or collapsed states seem to quickly change from one state to the other. The changes appear to depend on temperature, pressure, and the presence of solutes, proteins, and polysaccharides.5 If this is true, several anomalous features of water would be explained.

"Two other phenomena are challenging current scientific certainties in relation to water, and other liquids too: Hofmeister effects and dissolved gases.

***

"Around 1888, Franz Hofmeister and his collaborators in Prague performed a simple experiment precipitating egg-white albumin in the presence of different salts, at the same concentration. They observed that solutions of some salts precipitated albumin more effectively than others. A year later in Saint Petersburg, Ivan Mikhaylovich Sechenov realized that scarcely soluble compounds such as gases possess different solubilities in salt solutions, depending on the nature of the electrolyte.

***

"The structure of water is elusive. The array and strength of interactions that keep water molecules together with such high cohesive energy determines their anomalous properties and, in particular, their interactions with solutes, whether neutral or ionic.

"It is not only life that relies on water. In the natural inorganic world, the most abundant minerals are silicates, carbonates, sulfates, aluminum, magnesium, calcium, sodium, and potassium. In the Earth’s mantle, the most abundant elements are magnesium 23%, silicon 22%, iron 5.8%, calcium 2.3%, aluminum 2.2%, sodium 0.3%, and potassium 0.3%. These ions are all strong or mild kosmotropes with important hydration layers. In contrast, the poorly hydrated chaotropes are not common in the natural inorganic world or in living systems. The large quantities of water found on earth and the origins of life may depend on these features.

Comment: Water is weird. Why do two gasses become a complex liquid? Nitrogen and oxygen, two gases make a gaseous product. My guess is God purposely created water with its strange and probably unknown properties first as as preparation for the subsequent creation of life. As we study natural products in great depth, what God has done makes lots more sense and removes questions we might have.

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Another review:

https://www.chemistryworld.com/features/the-weirdness-of-water/4011260.article?utm_sour...

"Water, the most commonplace of liquids, is also the strangest. It has at least 66 properties that differ from most liquids – high surface tension, high heat capacity, high melting and boiling points and low compressibility. One school of thought is that water is not a complicated liquid but ‘two simple liquids with a complicated relationship’. For some, this statement contradicts the basic principles of physical chemistry; for others it explains just why water behaves in such an anomalous way.

***

"As you cool a liquid, its density increases, and its heat capacity and compressibility decrease. ‘Almost all liquids on the planet behave like that. Except for water.’ This strangeness comes into focus as water is cooled to 4°C, where its density reaches a maximum, below which it starts to decrease again.

"The explanation chemists are taught is that while most liquids are disordered, with their molecules constantly rearranging, water differs due to its network of hydrogen bonds. Hydrogen bonds have a strength in between stronger covalent bonds and weaker dipole-induced interactions. Unlike the latter, they are directional, with each hydrogen atom pointing towards an electron pair on an oxygen atom.

‘'It’s a lot of hydrogen bonding for such a small molecule,’ says Martin Chaplin,

***

"There is still no consensus among physical chemists as to how water behaves. This may seem a purely esoteric debate, but water’s unusual properties, particularly at very low temperatures, do have implications for other areas of sciences. ‘It affects climate models [at] high pressure, [and] extra-terrestrial water [that] we might find on other planets, or [water in] nano-confinement,’ says Russo. For example, a recent study showed that water at the surface of droplets was much more ordered than bulk water and in a comparable state to supercooled water with strong hydrogen bonding, even at room temp erature.

"Whether a mixture of two liquids or just one, water’s properties are also fundamental to biology. ‘Water is the thing that gives [nucleic acids] their interesting structure and properties, and it’s the same with proteins,’ says Chaplin. Life itself has flourished because ice is less dense than water, allowing organisms to survive underneath floating ice layers. ‘What is interesting is we are peering into the region where life exists when [water’s anomalous behaviour] pops up,’ says Nilsson. According to his two-state model, it is only at temperatures below 50°C that water becomes a mixture of low- and high-density liquid and this is also the temperature region at which life exists. ‘Is this a coincidence, or is there something significant about that?’ asks Nilsson. ‘We don’t [yet] know.'’

Comment: Water is just like quantum mechanics, vital to reality and just as weird. God works in very mysterious ways to create this reality.

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Here are five listed:

http://oceans.nautil.us/feature/568/five-things-we-still-dont-know-about-water?mc_cid=7...

"1. How Many Kinds of Ice Are There?
At latest count, there are 17 different crystalline forms of solid water. However, only one form—Ice Ih—exists commonly on Earth outside of the laboratory. A second crystalline form called Ice Ic is present in very minor amounts in the upper atmosphere, and another 15 forms occur only at very high pressures.

***

"The application of pressure to tetrahedral substances, including crystalline ice, elemental carbon, silicon, and phosphorus, can collapse low-density solid forms into a variety of structures of sequentially higher density, presumably until the close-packed limit is reached. This produces the 17 forms of crystalline ice we have observed so far. Are there more to discover?

"2. Are There Two Kinds of Liquid Water?
Several decades ago, Japanese scientists claimed to have observed transitions between two phases of amorphous ice under high pressure. Since we believe that amorphous ice is essentially a frozen snapshot of the corresponding liquid, this observation implied that two types of liquid water must exist: normal, low-density water, and a compact high-density form analogous to high-pressure amorphous ice.

"Subsequent simulations have supported this claim. They investigated water whose temperature was below freezing, but above its “homogeneous nucleation temperature” (the temperature below which liquid water cannot exist). In this so-called “deeply supercooled” region, scientists saw evidence for a phase transition between two liquid forms of water.

***

"3. How Does Water Evaporate?
The rate of evaporation of liquid water is one of the principal uncertainties in modern climate modeling. It determines the size distribution of water droplets in clouds, which, in turn, determines how clouds reflect, absorb, and scatter light.

"But the exact mechanism for how water evaporates isn’t completely understood. The evaporation rate is traditionally represented in terms of a rate of collision between molecules, multiplied by a fudge factor called the evaporation coefficient, which varies between zero and one. Experimental determination of this coefficient, spanning several decades, has varied over three orders of magnitude. Theoretical calculations have been hampered by the fact that evaporation is an extremely rare event, requiring prohibitively long and large computer simulations.

***

"4. Is the Surface of Liquid Water Acidic or Basic?
There is something remarkable about the mist surrounding Niagara Falls: The individual droplets move as if they are negatively charged. The same is true for most waterfalls. This has long been interpreted as evidence for the accumulation of negative hydroxide (OH-) ions at the droplet surfaces, which would mean that the surfaces are basic—with a pH value greater than the 7 of neutral water. In fact, this thinking has become dogma within the community of colloid scientists.

"The surface of liquid water contains a larger number of broken hydrogen bonds, which produce a rather different chemical environment than that found in the bulk. But recent experiments and calculations suggest that hydrated protons (H+) actually dominate the liquid water surface, producing an acidic (less than 7) pH and a positively charged surface, rather than a basic, negatively charged surface.

"Many important processes in chemistry and biology, like atmospheric aerosol–gas exchanges, enzyme catalysis, and transmembrane proton transport, involve proton exchanges at the water surface, and explicitly depend on the pH at the water’s surface—a quantity which is currently unknown.

"5. Is Nanoconfined Water Different?
Water isn’t always sloshing around in giant oceans. Both in nature and in man-made devices, water is often confined to unimaginably tiny spaces, like reverse micelles, carbon nanotubes, proton exchange membranes, and xerogels (which are highly porous glassy solids).

"Both experiment and calculation seem to indicate that water confined by solid walls to tiny regions of space, whose size is comparable to that of a few hundred molecules, begins to exhibit quantum mechanical effects, including delocalization and quantum coherence. These properties are strikingly different from those of bulk water, and could influence everything from biological cells to geological structures. It could be also be of considerable practical significance, for example in designing more efficient desalinization systems.

"Current results remain somewhat ambiguous, however, and more work in this area remains to be done in order to determine the nature of water under confinement.

Comment: Vital for life with many supportive characteristics. Designed that way?

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Another study:

https://www.sciencedaily.com/releases/2020/07/200716144719.htm

"A new study provides strong evidence for a controversial theory that at very cold temperatures water can exist in two distinct liquid forms, one being less dense and more structured than the other. Researchers conducted computer simulations of water molecules to discover the critical point at the transition between the two forms.

***

"Now a new study provides strong evidence for a controversial theory that at very cold temperatures water can exist in two distinct liquid forms, one being less dense and more structured than the other.

***

"Water's oddities include that as water cools, it expands rather than contracting, which is why frozen water is less dense than liquid water. Water also becomes more squeezable -- or compressible -- at lower temperatures. There are also at least 17 ways in which its molecules can arrange when frozen.

"A critical point is a unique value of temperature and pressure at which two phases of matter become indistinguishable, and it occurs just prior to matter transforming from one phase into the other.

"Water's oddities are easily explained by the presence of a critical point, Debenedetti said. The presence of a critical point is felt on the properties of the substance quite far away from the critical point itself. At the critical point, the compressibility and other thermodynamic measures of how the molecules behave, such as the heat capacity, are infinite.

"Using two different computational methods and two highly realistic computer models of water, the team identified the liquid-liquid critical point as lying in a range of about 190 to 170 degrees Kelvin (about -117 degrees to -153 degrees Fahrenheit) at about 2,000 times the atmospheric pressure at sea level.

"The detection of the critical point is a satisfying step for researchers involved in the decades-old quest to determine the underlying physical explanation for water's unusual properties.

***

"'You can imagine the joy when we started to see the critical fluctuations exactly behaving the way they were supposed to," Sciortino said. "Now I can sleep well, because after 25 years, my original idea has been confirmed."

"In the case of the two liquid forms of water, the two phases coexist in uneasy equilibrium at temperatures below freezing and at sufficiently high pressures. As the temperature dips, the two liquid phases engage in a tug of war until one wins out and the entire liquid becomes low- density.

***

"Some of the odd behaviors of water are likely to be behind water's life-giving properties, Zerze said. "The fluid of life is water, but we still don't know exactly why water is not replaceable by another liquid. We think the reason has to do with the abnormal behavior of water. Other liquids don't show those behaviors, so this must be linked to water as the liquid of life."

"The two phases of water occur because the water molecule's shape can lead to two ways of packing together. In the lower density liquid, four molecules cluster around a central fifth molecule in a geometric shape called a tetrahedron. In the higher density liquid, a sixth molecule squeezes in, which has the effect of increasing the local density.

"The team detected the critical point in two different computer models of water. For each model, the researchers subjected the water molecules to two different computational approaches to looking for the critical point. Both approaches yielded the finding of a critical point."

Comment: A very strange liquid but extremely vital for life to exist. Must be purposeful.

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Water has two forms when cooled:

https://www.sciencenews.org/article/stop-motion-experiment-reveals-supercooled-water-du...

"Supercooled water may be a two-for-one deal.

"A long-standing theory holds that liquid water at temperatures well below freezing is composed of two different arrangements of molecules, one with high density and one with low density. Now, an experiment provides new evidence for that theory, researchers report in the Sept. 18 Science.

***

"The researchers conclude that the water’s behavior as it was heated and cooled could be explained by the coexistence of two different molecular arrangements, as previously predicted. However, the team hasn’t directly measured the density of those structures, so more work is still needed to confirm whether the theory is correct.

“'The combination of techniques is quite new and original,” says chemical engineer Pablo Debenedetti of Princeton University, who was not involved with the study.

"Better understanding the strange properties of supercooled water might help scientists understand water’s quirks. For example, unlike most substances, water expands when it freezes, making it less dense than its liquid form. That’s the reason why ice floats in your cup and why it sits atop a lake, leaving a liquid layer underneath that can shelter aquatic life over the winter.

“'Water is a very strange liquid,” says physicist Greg Kimmel, a coauthor of the study, also at the Pacific Northwest National Laboratory. “But everybody’s familiar with it, so we don’t really realize how weird it is.'”

Comment: Without water, life can't exist. Our bodies are over 70% water. Along with quantum mechanics it is one of God's very strange inventions to create us.

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1574 views

A good review article. Its not just sodium chloride:

https://inference-review.com/article/reading-seawater

"The ocean is not merely a receptacle for inputs from rivers and volcanoes, but a dynamic medium whose chemistry is modulated by processes far more complex than previously imagined. The salt in seawater is now known to include more than 40 elements, ranging in concentration from gold at 0.00008 parts per million to sodium at more than 10,000 parts per million.

"Oceanographers classify these elements into three groups: conservative, scavenged, and recycled.17 Conservative elements, which include the major constituents of seawater, such as sodium and chlorine, have residence times on the order of millions to hundreds of millions of years. Their residence times are much longer than mixing times, the period over which they are distributed via waves, currents, and eddies. If an element’s residence time is greater than its mixing time, its concentration will be fairly uniform throughout the ocean, and it can be considered to have reached a state of chemical equilibrium in seawater.

"Recycled and scavenged elements have much shorter residence times, on the order of hundreds or thousands of years.18 As a result, there is insufficient time for these elements to achieve equilibrium through mixing, and their concentrations vary according to geography and depth. Scavenged elements include aluminum, lead, mercury, and other metals. These elements are attracted to the surfaces of fine clay particles and are exported from shallow waters as the particles sink to the ocean floor. The chemical concentration of scavenged elements decreases with depth in the water column.

"The recycled elements exhibit the most interesting and complicated behavior of all the groups. These are the ingredients essential for life, such as carbon, copper, iodine, iron, nitrogen, phosphorous, and zinc. In the uppermost region of the ocean where almost all sea life can be found, these elements are limiting nutrients, whose scarcity makes them coveted commodities in the marine biosphere. Any of these elements lost by one organism will be snatched up by another, keeping their concentration in the water itself low. Over time, a fraction of these nutrients leaks into deeper and relatively uninhabited waters, and so the concentration of recycled elements generally increases with depth.

***

"Paleo-oceanographers now recognize that ocean chemistry has not remained strictly constant over time. The onset of the frigid Pleistocene epoch around 2.6 million years ago is thought to be linked to an increase in the salinity of the Atlantic Ocean as a result of the formation of the Isthmus of Panama. The isolation of the Atlantic from the less salty Pacific profoundly affected the global thermohaline circulation system, of which the Gulf Stream is one part.

***

"From the very beginning, the history of life on earth has been intertwined with that of seawater. All the mass extinction events evident from the fossil record have been linked to variations in ocean chemistry, such as widespread acidification, anoxia, and associated perturbations to the carbon cycle. The demise of the dinosaurs, for example, can be attributed in large part to oceans poisoned by the constituents of the carbon and sulfur-rich rocks vaporized by the Chicxulub impactor. For this reason, some of the changes in ocean chemistry observed during the Anthropocene ought to give pause. The magnitude of these changes are comparable to the Great Dyings of the geologic past.23 If not tears or sweat, seawater could perhaps instead be considered earth’s blood, its composition a proxy for the health of the planet."

Comment: The oceans are part of many stabilizing processes like a carbon cycle. Oceans are complex just like all of the parts of Earth.

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Another unique property described in how water is ionized in different ways that helps life:

https://www.nyu.edu/about/news-publications/news/2018/august/the-behavior-of-water--sci...

"A team of scientists has uncovered new molecular properties of water—a discovery of a phenomenon that had previously gone unnoticed.

"Liquid water is known to be an excellent transporter of its own autoionization products; that is, the charged species obtained when a water molecule (H2O) is split into protons (H+) and hydroxide ions (OH−). This remarkable property of water makes it a critical component in emerging electrochemical energy production and storage technologies such as fuel cells; indeed, life itself would not be possible if water did not possess this characteristic.

"Water is known to consist an intricate network of weak, directional interactions known as hydrogen bonds. For nearly a century, it was thought that the mechanisms by which water transports the H+ and OH− ions were mirror images of each other – identical in all ways except for directions of the hydrogen bonds involved in the process.

"Current state-of-the-art theoretical models and computer simulations, however, predicted a fundamental asymmetry in these mechanisms. If correct, this asymmetry is something that could be exploited in different applications by tailoring a system to favor one ion over the other.

"Experimental proof of the theoretical prediction has remained elusive because of the difficulty in directly observing the two ionic species. Different experiments have only provided glimpses of the predicted asymmetry.

"A team of scientists at New York University, led by Professor Alexej Jerschow and including Emilia Silletta, an NYU postdoctoral fellow, and Mark Tuckerman, a professor of chemistry and mathematics at NYU, devised a novel experiment for nailing down this asymmetry. The experimental approach involved cooling water down to its so-called temperature of maximum density, where the asymmetry is expected to be most strongly manifest, thereby allowing it to be carefully detected.

"It is common knowledge that ice floats on water and that lakes freeze from the top. This is because water molecules pack into a structure with lower density than that of liquid water—a manifestation of the unusual properties of water: the density of liquid water increases just above the freezing point and reaches a maximum at four degrees Celsius (39 degrees Fahrenheit), the so-called temperature of maximum density; this difference in density dictates that liquid is always situated below ice.

"By cooling water down to this temperature, the team employed nuclear magnetic resonance methods (the same type of approach is medically in magnetic resonance imaging) to show that the difference in lifetimes of the two ions reaches a maximum value (the greater the lifetime, the slower the transport). By accentuating the difference in lifetimes, the asymmetry became glaringly clear.

"As noted previously, water consists of one oxygen atom and two hydrogen atoms, but the hydrogen atoms are relatively mobile and can hop from one molecule to another, and it is this hopping that renders the two ionic species so mobile in water.

"In seeking explanations for the temperature-dependent characteristics, the researchers focused on the speed with which such hops can occur.

"'Prior research had indicated that two main geometrical arrangements of hydrogen bonds (one associated with each ion) facilitate the hops. The researchers found that one of the arrangements led to significantly slower hops for OH− than for H+ at four degrees Celsius. Being that this is also the temperature of maximum density, the researchers felt that the two phenomena had to be linked. In addition, their results showed that molecules’ hopping behavior changed abruptly at this temperature.

"The study of water’s molecular properties is of intense interest due to its central role in enabling physiological processes and its ubiquitous nature,” says Jerschow, the corresponding author of this study. “The new finding is quite surprising and may enable deeper understanding of water's properties as well as its role as a fluid in many of nature’s phenomena.'”

Comment: This strange liquid, water comes from two gasses. It is too strikingly strange to have happened by chance; designer required, a designer who planned for life to exist.

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2771 views

Another very complex article filled with dense equations about water's properties:

https://inference-review.com/article/water-and-its-mysteries#footnote-1

"There are very few things that modern science does not understand. One of them is consciousness; the other is water.1 In the case of consciousness, the hard problem is designing good experiments; in the case of water, finding a theory that explains its properties.

***

"Strange. A decrease in temperature suggests a decrease in the average speed of molecules in water; and this, in turn, suggests a decrease in volume as molecules are attracted to one another. With water, the opposite is observed. A decrease in speed induces repulsion between water molecules and not attraction.

***

"What makes water unique for biology is this wide palette of minima or maxima between –42°C and 100°C. It remains a theoretical challenge to explain why large mean square fluctuations in entropy, volume, and temperature, and small mean square fluctuations in pressure are observed as the average speed of water molecules decreases.

"Chemists are not without clues. A first: all thermodynamic response functions seem to diverge toward a singular temperature of about 228 K at ambient pressure. A second: all water anomalies are linked to the existence of hydrogen bonds (H-bonds) between water molecules. The idea of performing molecular dynamics simulations in order to predict phase diagrams is, if not inevitable, then, at least, natural. Under simulation, H-bonds are characterized by a van der Waals component ε describing the universal attraction between molecules, a directional component J describing the decrease in potential energy specific to hydrogen bonding (two-body interactions), and a component Jc describing the cooperative character of H-bonds (three-body interactions).

***

Comment: There are two forms of water, low and high density:

"It follows that LDW has a more rigid tetrahedral structure based on linear H-bonds than HDW. Recent experiments have shown that a high-pressure phase ice VIII transforms to a low-density liquid under rapid and complete release of pressure at 140–165 K.14 X-ray scattering data suggests that the structure of this liquid was very similar to that of low-density amorphous ice, with no variation of the spectrum with temperature consistent with a fully developed tetrahedral network. By contrast, deeply supercooled water showed a spectrum that displayed strong temperature dependences. These changed continuously due to structural fluctuations between HDW and LDW, and caused water anomalies around the Widom line.

***

"What pushes water molecules to form two liquids of different densities having quite different local structures and dynamics? This is not yet understood. Water anomalies reflect the properties of hydrogen bonding, and it is just the question why hydrogen bonds exist in the first place that remains unclear. This problem has already been treated in this journal, and the key point seems to be the capability of water molecules to undergo electronic self-excitations using vacuum virtual energy.19 Quantum field theory allowing direct coupling between matter and photons predicts that two different shapes could be expected for water molecules. When the water molecule is not excited by the vacuum’s virtual energy, it adopts an almost spherical shape that is perfectly suited for strong van der Waals interactions typical of HDW-type liquids. On the other hand, self-excitation toward Rydberg states localized onto the oxygen atom using the vacuum’s virtual energy leads to the tetrahedral structure typical of hydrogen bonding. It is this second tetrahedral shape that displays a strong cooperative behavior associated with quantum coherence typical of the other, LDW type of liquid."

Comment: Vital for life and not understood. I've left out the complex physics discussions

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2298 views

It has very strange properties:

http://nautil.us/blog/-why-water-is-weird

"In their 2018 study, 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.

"The researchers, with the benefit of supercomputers, were able to tweak and untune a computational model of water, making it behave like other liquids. “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.” The paper’s title spells this out: “Water-like anomalies as a function of tetrahedrality.”

"Nautilus asked Richard Saykally, a chemist at U.C. Berkeley, why these peculiarities make the liquid so ripe for scams and fanciful speculations. The ancient Greeks thought water was one of the four “essential” elements, the others being earth, air, and fire. Homeopathy, which purports to cure illness using small doses of disease-causing substances dissolved in water, evolved out of this, Saykally said. But there are more modern magical claims about so-called “structured” or “hexagonal” water. Some “wellness” practitioners claim humans age in part because we don’t replenish our stock of structured water. Depending on water’s structure, they say, it can penetrate your cell walls more effectively and has all kinds of health benefits.

“'There’s no scientific basis to that at all,” Saykally said. “You can’t make structured water. Doesn’t make any sense because the hydrogen bond in water lives for a few picoseconds—10-12 seconds—and these hydrogen bond structures of water are rearranging very rapidly so you don’t have water clusters existing as isolated entities in water despite a lot of these claims.”

Comment: There is fine tuning in other ways than cosmological; Water is essential for life and it is weird. Probably designed that way.

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2228 views

Expanded and floats:

https://bigthink.com/starts-with-a-bang/ice-skating-miracle-physics/?utm_campaign=swab&...

"...if you put thin blades on the bottoms of your shoes — ... As long as you can remain on your feet, with only your blades touching the ice, you’ll find that you can control your motion relatively easily, simply by applying forces through your feet (and the blades) to the ice down below. You can speed up, slow down, or change direction at will, and only if you fall or lose control of your skates (and body) will you wind up in a similar situation to the no ice skate case. It might seem miraculous, but there’s physics behind what you’re experiencing at each and every step. Here’s how it all works.

***

"Under different temperature and pressure conditions found on Earth and elsewhere in the Universe, different possibilities arise for how those various molecules bind together, creating a massive variety of possible configurations. At present, there are a whopping 20 known phases of ice, including:

"Ice Ih, which is normal hexagonal crystalline ice and the most common form of ice found on or near Earth’s surface,

"Ice Ic, which is a cubic crystalline variant of ice whose oxygen atoms are arranged in a diamond structure, that often appear at the lower temperatures found in the upper atmosphere,
And amorphous ice, which has no crystalline structure and is sometimes formed at ambient atmospheric pressure, in addition to the higher-pressure/temperature phases of ice: Ice 2 through Ice 18.

"However, it’s the most common form of ice, plain old Ice Ih, that’s relevant for the problem of ice skating. Normally, under this configuration, the water molecules within ice are arranged in a hexagonal crystal lattice, and adding new water molecules to these icy structures will simply result in the growth of the main crystal in the same ongoing pattern. Adding more molecules won’t change the structure of your ice,

***

"...the most common fate of hexagonal crystalline ice — the type of ice found on Earth’s surface — is that either heating it or compressing it will simply cause it to melt.

***

"This is incredibly important, and forms the physical basis for how ice skating can physically occur. If water/ice behaved like most materials, then simply by applying greater and greater amounts of pressure to the liquid phase would force it into a solid phase, as the atoms/molecules inside would achieve a more tightly-packed configuration.

"But water is different than most materials, in that when you freeze it, it actually expands from a liquid phase into a solid phase, occupying more volume as a solid than it did as a liquid. And this means, even if you apply a tremendous amount of pressure to liquid water, it remains liquid. But if you apply that same amount of pressure to solid water (ice), it can transition into a liquid phase.

***

"That’s where the idea of ice skates becomes so powerful. Instead of distributing the force from your body, which can approach nearly 1000 Newtons for an average human being, over a substantial area (your footprint), they instead decrease your area tremendously: down to a long, thin “blade” of metal. If a typical skate blade is 30 centimeters long (about 1 foot) but only about 1 millimeter thick, that can create a pressure of up to three million pascals (a Newton-per-square meter) for a typical human who puts their weight down on one ice skate: about 30 times the normal amount of atmospheric pressure!

***

"First, the top layer of ice, the one in contact with their skates, turns to liquid just as their skate glides over it.

"The fact that there’s a thin, lubricating layer of liquid water between the skate above it and the solid ice beneath it reduces the skater’s friction even further.

"The liquid water, as we discussed earlier, fills in the small imperfections in the ice, creating an even smoother, lower-friction interface.

"Because there’s a decrease in the ice’s volume when it melts into the liquid phase, this creates a small “groove” in the ice for the skater to travel in.

"And finally, when the skate finishes passing over the portion of the ice that was melted, the sudden “drop” in pressure immediately causes the melted water to re-freeze, becoming ice once again.

"In other words, even though we call it ice skating, the reason it’s so successful is because the skater is actually skating atop a thin layer of liquid water!

***

"If water and ice were more like the typical materials found throughout the Universe, where their solid phase is denser and has their component particles more tightly packed than their liquid phase, then ice skates would never work. Increasing the pressure over a thin region of surface would simply compress the solid, rather than melting it into a liquid phase. That’s the key property — rarely found in nature, but belonging to water and only a few other chemical compounds — that enables the high-pressures exerted by all of a human’s weight being focused down onto a narrow blade to melt, and glide over, the ice."

Comment: water's strange characteristics make it vital for life. Note that hydrogen and oxygen were some of the earliest formed elements. That is how a designer would work, set up important items early on in preparation for the future.

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Water; required for life (Introduction)