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The physics of water

  1. Oct 11, 2007 #1
    I was wondering what are the physical properties of water that make it so different from other liquids?

    I stand to be corrected on this list, but i think water is unique in the following attributes;

    - Water is in dynamic equilibrium between the liquid, gas and solid states at standard temperature and pressure, and is the only substance found naturally on Earth to be so.
    - It has the highest natural Electronegativity
    - It is the only natural liquid that gains volume when frozen
    - It is the only liquid that supports all known life
    - It is the strongest natural solvent
    - Second highest specific heat capacity of any known chemical compound
    - Water has a very high surface tension compared to other liquids

    It seems to be a lot of characteristics for something that is, in essence, just one oxygen and two hydrogen atoms. Why is it so unique?
  2. jcsd
  3. Oct 11, 2007 #2


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    The H20 molecule has a large polarizability,
    and also readily ionizes.
  4. Oct 13, 2007 #3
    I found a link that should help. http://www.ozh2o.com/h2chem.html [Broken] Enjoy!
    Last edited by a moderator: May 3, 2017
  5. Oct 13, 2007 #4

    you mean it is a polar molecular?
  6. Oct 14, 2007 #5

    Claude Bile

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    The simplicity of the structure is the key to it's uniqueness. Complex molecules (such as the Hydrocarbon family) are more likely to have similar chemical "cousins" because the addition of an atom or bond is less of a perturbation to the original molecule if it is complex, than if it is exceedingly simple.

    I'm not a chemist, and there are probably other factors, but the trend that simplicity = uniqueness makes sense in my mind.

  7. Oct 16, 2007 #6


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  8. Oct 16, 2007 #7
    Water is a perfect example of hydrogen bonding too, because almost all the lone pair in each molecule are involved in hydrogen bonding..And maybe because of this unique property, water is known as universal solvent..:wink:
  9. Oct 17, 2007 #8
    Which is the first ? And what is its heat capacity ?
  10. Oct 17, 2007 #9


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    H20 is a really strange molecule with lots of interesting properties. It is e.g. quite amazing that such a simple structure can form so many different solid phases (I think there were 11 at last count).
    If you are really interested I cn recommend the book "H20" by Phillip Ball.
    It is pop sci but good pop sci (which is rare).
  11. Oct 17, 2007 #10
    i think that ammonia is the first, followed by water. specific heat capacity is the amount of heat energy required to increase the temperature of a substance by a certain temperature interval. its basically its ability to absorb heat.

    thanx for the info. Wikipedia says there are 14 types, and some of them have some interesting characteristics, Ice X1, is a type of of hexagonal ice and is ferroelectric. Is this another unique property of water, that it can form into many different solid states?
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