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Single atom

  1. Aug 25, 2004 #1

    mee

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    If there is a single atom of water or some substance, can it have the properties of a solid gas or liquid? Or is it a seperate state?
     
  2. jcsd
  3. Aug 25, 2004 #2

    LURCH

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    Since the states of matter the properties of interaction between particles within that matter, I'm fairly certain that a single atom cannot be considered to exhibit the properties of any of these states.

    Much like people, atoms are not considered to have an identity if they are single.

    I'm sorry... did that sound a little bitter?
     
  4. Aug 25, 2004 #3

    mee

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    Could this mean that much of the interstellar "gas" is the no-state of singular atoms?
     
  5. Aug 25, 2004 #4
    I've never before heard of a single atom of water, but I have heard of a single molecule of water. How do we make a single atom of water?
     
  6. Aug 25, 2004 #5

    mee

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    Alright smarty.
     
  7. Aug 25, 2004 #6
    Sorry! Meant to tease just a wee little bit.
     
  8. Aug 26, 2004 #7

    mee

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    Thanks. :)
     
  9. Aug 26, 2004 #8

    LURCH

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    I think that by using (or thinking) the term "interstellar", we automatically set our thoughts to a very large scale. On this scale, the individual atoms in interstellar space do occasionally collide. In these collisions, the atoms behave as they would in a gass, so the interstellar medium is indeed a very thin gass.
     
  10. Aug 26, 2004 #9

    mee

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    Any idea why this would be if they are at temperatures that would normally make them a solid?
     
  11. Aug 26, 2004 #10

    reilly

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    Can a V-6 engine get me from here to Chicago? No if it is stand-alone. Yes if it is part of a car.

    Regards,
    Reilly Atkinson
     
  12. Aug 26, 2004 #11

    mee

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    I'm not sure I understand Reilly. A bit obscure.
     
  13. Aug 27, 2004 #12
    One of the properties of solid gas and liquids is their temperature, so I suppose you could consider a -100 degree single molecule of H2O as a molecule of ice and a 200 degree single molecule of H2O as a molecule of vapor. But frankly, states of mater are best defined when you have a bunch of molecules, or else a single C could be either graphite or diamond.

    A molecule can be said to possess temperature though, best expressed as energy.
     
  14. Aug 29, 2004 #13

    mee

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    So the potentially freezing, and therefore probably solid, interstellar medium is a gas?
     
  15. Aug 29, 2004 #14
    You could say that, a gas or a plasma or perhaps a combination of both. Interstellar atoms can be affected by stellar radiation (cosmic rays etc.), so they make a gas or a plasma, depending on where there are (what kind of ray bombardment it receives).

    H2O molecules in interstellar space for example obviously need to meet other to form solid ice, but such a meeting doesn't happen as often as it could on Earth (low density and pressure), so until then they remain a very cold gas that has the potential to form ice. Each molecule may collide with other stuff that give them energy or ionize them (photon) or that destroy them (perhaps cosmic ray particles) before meeting other H2O, but meeting other H2O first could make them become a small chunk of ice (Comets are ice, how do they form?). Whether a random interstellar molecule spends most of its life ionised (unit of plasma) or not (unit of gas) I am not sure, but I would say probably a gas.
     
  16. Aug 29, 2004 #15

    mee

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    Thanks Gonzolo. :)
     
  17. Aug 30, 2004 #16

    LURCH

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    Yes, but it's only an "idea". The key is in the word "normally", I think. In interstellar space, atoms are in an environment of very low (almost no) pressure. Lowering pressure reduces the boiling point of a substance, near-vacuum makes things boil or evaporate at temps where they would freeze under more familliar conditions. But this is only a geuss on my part.
     
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