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lightest gas?

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  • 05-02-2005 10:03pm
    #1
    ublinina
    Closed Accounts Posts: 21 ✭


    What is the lightest gas - is it helium or hydrogen?


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    #2
    David19
    Registered Users Posts: 925 ✭✭✭David19


    Hydrogen.


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    #3
    ublinina
    Closed Accounts Posts: 21 ✭ublinina


    Is this the lightest of all gases ? Does it make any overall difference that it is diatomic?


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    #4
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,814 Mod ✭✭✭✭Capt'n Midnight


    Each mole of H2 weight 2g and has a volume of ~22 litres.

    each molocule has 2 electrons and 2 protons and no neutrons (very little deutrium or tritium anyway)

    the next lighest atom is Helium3 which weighs in at a whopping 3g per 22litres.
    normal helium weighs 4g twice the weight of hydrogen.
    Methane (natural gas) is also lighter han air


    Uranium Hexafluoride is probably the heaviest gas at room temperature..

    [edit] the chemical reaction that gives out most energy per weight of reactant is H + H = H2 , monotomic hydrogen would make ideal rocket fuel !


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    #5
    Horsefumbler
    Registered Users Posts: 1,823 ✭✭✭Horsefumbler


    yeah but lets talk about cubanes ;)


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    #6
    Professor_Fink
    Registered Users Posts: 861 ✭✭✭Professor_Fink


    I take it you're excluding photon gases, electron gases, ionized gases and plasmas?


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    #7
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,814 Mod ✭✭✭✭Capt'n Midnight


    Professor_Fink wrote:
    I take it you're excluding photon gases, electron gases, ionized gases and plasmas?
    I'd suppose it's at room temperature

    But Hydrogen is still lighter (at the same temperature) than any other ionised gas or plasma.

    unless you got your hands on a bag of north monopoles or gravitions then they'd be even lighter, well you wouldn't be able to put them on the scales.

    if things get lighter as they get further away from the speed of light, how much would tachyons way ??


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    #8
    Professor_Fink
    Registered Users Posts: 861 ✭✭✭Professor_Fink


    Capt'n Midnight wrote:
    I'd suppose it's at room temperature

    But Hydrogen is still lighter (at the same temperature) than any other ionised gas or plasma.

    unless you got your hands on a bag of north monopoles or gravitions then they'd be even lighter, well you wouldn't be able to put them on the scales.

    if things get lighter as they get further away from the speed of light, how much would tachyons way ??

    Photons don't have inertial mass, so I think they win outright. There is no evidence that tachyons are anything more than a mathematical relic. I'm not going to even comment on monoploes except to say that Maxwell's equations appear to work quite nicely, thank you. And Hydrogen is not lighter than an electron-proton plasma.


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