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Carbon Vapor and Gaseous Carbon

  1. Feb 12, 2005 #1
    Is it possible to maintain pure carbon gas at room temperature? Suppose I start with a vacuum chamber and allow a small amount of hot, gaseous carbon vapor inside it, but only enough so that it remains gaseous at normal room temperatures - is that possible to do? Where can I find formulas to let me know how much volume of vacuum space is needed and how many carbon atoms it can contain and still be gaseous @ room temperatures?

  2. jcsd
  3. Feb 12, 2005 #2


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    No, it's not possible to have (stable) gaseous (or even liquid) carbon at room temp.

    Your above described approach will not work. As the temperature drops (and with it the kinetic energy of the gas molecules), the molecules will eventually condense into solid graphite....even at absolute vacuum.

    Look up a phase digram for carbon. http://phycomp.technion.ac.il/~anastasy/teza/teza/node5.html

    The vapor phase does not exist at any pressure at room temperature. Evacuation only lowers the sublimation temerature from about 5500K to about 4000K.
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