Can carbon in the form of graphite melt or even boil? Under what experimental conditions? I ask this question because I found in a very serious book (Tables CRM Commission romande de chimie) information that I do not understand:

  • sublimation at 3650 ° C
  • boiling at 4827 ° C

But if the carbon sublimates at 3650 ° C, how does it boil? Is the work already done? How valid are these values. thank you in advance

  • 1
    $\begingroup$ That book more pretends to be serious. You are right, carbon cannot boil at 4827°C if it already sublimes at 3650. The fact is that carbon has it's triple point somewhere around 11 MPa and 4600°C. (wikipedia gives +-300 on that temperature. It's extremely difficult to maintain such a pressure and temperature at the same time, let alone measure anything.) $\endgroup$
    – Karl
    Dec 7, 2020 at 20:01
  • 1
    $\begingroup$ Don't forget, different behaviours are possible under different conditions (eg pressure). What conditions did the source specify? $\endgroup$
    – matt_black
    Dec 7, 2020 at 22:08
  • $\begingroup$ Mithoron's reference displays a diagram showing that no liquid carbon can exist at less than 100 atm, whatever the temperature. Carbon sublimes at ordinary pressures. $\endgroup$
    – Maurice
    Dec 8, 2020 at 17:27


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