Gas/liquid...

Discussion in 'Chemistry' started by Beer w/Straw, Jul 22, 2018.

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  1. origin Heading towards oblivion Valued Senior Member

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    Ice is less dense than liquid water because it forms a Hexagonal crystal structure which is an 'open' structure. In solid ice each water molecule is hydrogen bonded to 4 other water molecules and in liquid water each of the water molecules is hydrogen bonded on average to about 3.5 other water molecules. So in ice the the molecules are held slightly farther apart making the ice less dense.
     
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  3. Beer w/Straw Transcendental Ignorance! Valued Senior Member

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    So, ice, is not H2O, but bound to H2O molecules?
     
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  5. origin Heading towards oblivion Valued Senior Member

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    Water, steam and ice are all made of H2O. In steam or water vapor the molecules are not bonded, each water molecule is free to move around in the air. In water the H2O molecules break and reform bonds. That is why the water is a liquid, the breaking and reforming of bonds allow it to flow. On average there are about 3.5 hydrogen bonds for each molecule. In ice the bonds do not break, a rigid crystal lattice is formed with each H2O molecule bonded to 4 other H2O molecules.
     
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  7. Beer w/Straw Transcendental Ignorance! Valued Senior Member

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    Uh... Is there any quantum leap that releases heat when water becomes ice?
     
  8. sideshowbob Sorry, wrong number. Valued Senior Member

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    I fail to understand why you think the density of water has anything to do with CO2 in the atmosphere. Please explain the linkage.
     
  9. origin Heading towards oblivion Valued Senior Member

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    Yes there is a big jump in the amount of energy released when water turns to ice compared to changing the temperature of water.
    To lower 1 kg of water 1 degree C, you must remove 4.19 kJ of heat energy.
    To change 1 kg of water at 0 C to 1 kg of ice at 0 C, you must remove 334 kJ of heat energy.
     
  10. Beer w/Straw Transcendental Ignorance! Valued Senior Member

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    Gravity for fucks sake.
     
  11. sideshowbob Sorry, wrong number. Valued Senior Member

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    That says nothing.

    There is CO2 in the atmosphere. There is H2O in the atmosphere. Neither is liquid. How does liquid enter into it?
     
  12. Beer w/Straw Transcendental Ignorance! Valued Senior Member

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    You don't mention gravity?
     
  13. sideshowbob Sorry, wrong number. Valued Senior Member

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    What has gravity got to do with it? Gravity doesn't pull CO2 down out of the atmosphere. Gravity doesn't pull H2O down out of the atmosphere. What has gravity got to do with it?
     
  14. Beer w/Straw Transcendental Ignorance! Valued Senior Member

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  15. sideshowbob Sorry, wrong number. Valued Senior Member

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    If you're going to ask questions, you have to learn to understand your own questions.
     
  16. Seattle Valued Senior Member

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    If a gas is lighter than air, gravity doesn't cause it to end up on the ground. The heavier column of air is between the two.

    If it's heavier than air such as CO2 much of it does settle to the ground. Up higher in the atmosphere it's mixed with other gasses and it moves around , it may behave differently due to temperature and pressure differences.

    What is your ultimate question? Is it why is CO2 a problem in the atmosphere when the subject is ozone depletion and why doesn't all the CO2 end up on the ground in the first place?

    If you have an actual question why can't you ask it rather than responding with one word such as "gravity"?
     
  17. Beaconator Valued Senior Member

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    This is mostly an assumption but hydrogen should be able to expand more than either carbon or oxygen.
     
  18. exchemist Valued Senior Member

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    Ballocks.
     
  19. origin Heading towards oblivion Valued Senior Member

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    Agreed!
    1 mole of ideal gas molecules will occupy the same volume (22.4L) when at standard temperature and pressure. Most real gases maintain this relationship or are very close to it, at STP.
     
  20. Beer w/Straw Transcendental Ignorance! Valued Senior Member

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    Is there another molecule that expands when cooled?
     
  21. DaveC426913 Valued Senior Member

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    Elements that expand on freezing are silicon, gallium, germanium, antimony, bismuth and plutonium.
     
  22. Beer w/Straw Transcendental Ignorance! Valued Senior Member

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    But not hydrogen or oxygen??

    :EDIT:

    Also I said molecule not element.
     
    Last edited: Dec 12, 2018
  23. DaveC426913 Valued Senior Member

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    No. The expansion of water is an emergent property, not inherent in O or H.

    I know. That's why I italicized elements, because I didn't have the exact answer to the question you asked.
     
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