Why can we not say Water exist in 4 phases

Discussion in 'Chemistry' started by timojin, Dec 16, 2015.

  1. origin Trump is the best argument against a democracy. Valued Senior Member

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    Clouds can form at ground level to over 12,000 m. The temperature of a cloud can be 20c to -40c.
     
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  3. DaveC426913 Valued Senior Member

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    Water is water. As a liquid it has no structure, though it still clings together by surface tension. Its structure changes when it crystalizes.

    But does this mean you accept condensation as a fact of physics?
     
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  5. timojin Valued Senior Member

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    As I said before I have done quite distillation and during distillation you collect your distillate by condensation , I know when vapor distillate change to liquid a latent heath of vaporisation is given off. So in the cloud there are a large amount of particles of water . So how do you do to bring this particles together and make them to come down as rain >
    Particles of water are about , and a typical cloud condensation nucleus (aerosol) is on the order of 0.0001 mm or 0.1 µm or greater in diameter. The number of cloud condensation nuclei in the air can be measured and ranges between around 100 to 1000 per cubic centimetre. A rain drop is about 2mm on size , again what is the mechanism to bring from 0.0001 mm to 2mm.
     
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  7. exchemist Valued Senior Member

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    Coalescence.
     
  8. origin Trump is the best argument against a democracy. Valued Senior Member

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    You realize that the droplets of water are not static, they are moving from the air currents, right? So the droplets hit each other and then, as exchemist stated, they coalesce until they become large enough to fall from the cloud. Do you not believe this is how it works?
     
  9. timojin Valued Senior Member

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  10. DaveC426913 Valued Senior Member

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    Soo....

    Please Register or Log in to view the hidden image!

     
  11. timojin Valued Senior Member

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    Let say I have 0.00001 droplet and they are drifting and to for a rain drop 2 .0 mm then I need 20000 droplet to coalesce .
    Here is something to meditate
    https://en.wikipedia.org/wiki/Cloud_condensation_nuclei
    A typical raindrop is about 2 mm in diameter, a typical cloud droplet is on the order of 0.02 mm, and a typical cloud condensation nucleus (aerosol) is on the order of 0.0001 mm or 0.1 µm or greater in diameter. The number of cloud condensation nuclei in the air can be measured and ranges between around 100 to 1000 per cubic centimetre.
     
  12. timojin Valued Senior Member

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    You have to combine clouds and by combining you increase the concentration and if you induce agitation you increase the collision ( coales ) and then you get you rain . Otherwise let the droplet trif into the space.
     
  13. DaveC426913 Valued Senior Member

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    Did you just quote yourself??
    Immediately after quoting origin but providing no response?
     
  14. timojin Valued Senior Member

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    I don't know what are you asking . for some reason it skipped perhaps I pushed the wrong button
     
  15. timojin Valued Senior Member

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    http://www.ecnmag.com/news/2016/01/...=5068946&et_rid=%%subscriberid%%&location=top
    Three water states in comparison

    Using molecular dynamics simulations, the team headed by Prof Marx analysed how to study the Widom line experimentally by means of terahertz spectroscopy. They published their results in collaboration with the Polish Gdansk University of Technology in Physical Review Letters. The simulations were partially conducted at the Leibniz Supercomputing Centre in Munich.

    The theorists compared three states: the state of liquid water at room temperature; a supercritical state with high density; and a supercritical state with low density. The analyses revealed that the hydrogen bond networks between the hydrogen molecules are completely different in those three states.

    States differ with regard to size and number of water clusters

    In liquid water at room temperature, almost all hydrogen molecules are bound via hydrogen bonds. In supercritical water, however, isolated clusters are formed. They consist of water molecules that are bound inside the cluster via hydrogen bonds, but do not have any hydrogen bonds to other clusters.

    The number of clusters of different sizes differs between supercritical states with high and low density. Properties of the gas phase are prevailing in supercritical water with low density, those of the liquid phase in supercritical water with high density.

    The researchers simulated the vibrational spectra associated with the three states in the terahertz range, whose shape is largely determined by the structure of the hydrogen bond network. Experimentally, it is not possible to observe directly which factors affect the shape of the spectra on the molecular level. Theoretical chemistry can close this gap: the present study has shed light on the physical processes that determine the shape of the terahertz spectra of gas-like and liquid-like supercritical water.

    "Our simulations have shown that terahertz spectroscopy should be an ideal method for analysing the properties of hydrogen bonds in the supercritical state of water - on both sides of the Widom line," concludes Schran. "Moreover, our findings will help to interpret the underlying molecular processes in the measured spectra.
     
  16. ZMacZ Registered Senior Member

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    What about plasma ?

    serious pressured steam with high temp forced back into a somewhat liquid-ish state ? so close to doing fusion stuff..
     
  17. river Valued Senior Member

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    Just wondering ; can they isolate one molecule of water ?
     
  18. timojin Valued Senior Member

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    What are your basis for such question ?
     
  19. river Valued Senior Member

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    Because I asked the question " what is water " ?

    I get the chemical bonds answer all the time ; fine ; but why does a liquid form ; the bonds of hydrogen and oxygen are important ; obviously ; but something deeper within the water molecule is going on.
     
  20. timojin Valued Senior Member

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    Now I see your interesting question . Is H2O water ? I suppose not . Probably first it will go though dimerisation and then an aggregate of H2O becomes a water particle or nucleation after liberating latent heatat and forms liquid liquid water I suppose also . its behaviour will be different in vapor depending on the surrounding heat, the heat will tend to break the hydrogen bonding and will backward to dimer .
     
  21. DaveC426913 Valued Senior Member

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    Is H2 hydrogen? Yes. Same with any other molecule.

    H20 certainly has a lot of interesting properties in aggregate form. But that makes it no less water in single doses.
     
  22. river Valued Senior Member

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    No ; not whether H2O is water ; it is water ; water is a liquid ; let me put this differently .

    The liquid state of hydrogen is ; -273 kelvin ; the liquid state of oxygen is ; - 256 kelvin .

    Yet the molecule of water becomes liquid at room temperature.
     
  23. river Valued Senior Member

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    But what do we know of H2O IN single molecule form ; nothing ; nothing at all.
     

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