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Carbon has no liquid form at atmospheric pressure. Is this unique amongst naturally occurring elements?

The more interesting and vague question is, is this property somehow important or related to the many other amazing properties carbon has on Earth or just a coincidence?

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Have a look at a generic phase diagram, for a compound with one solid phase, one liquid phase and a gas phase:

            enter image description here

For the solid to go directly into the vapor phase (sublimation) at ambient pressure upon heating, you thus need its triple point to have a higher pressure than atmospheric pressure, i.e. ~1 bar.

Looking at this partial table of element triple points, arsenic is another element that sublimes at ambient pressure. Iron would seem to qualify, but it has more phases that reported in the table, and the full phase diagram indicates that it does not sublime at ambient pressure.

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  • $\begingroup$ IODINE! gotta love purple fumes :D $\endgroup$
    – Tomcat
    Commented Aug 31, 2013 at 23:48
  • $\begingroup$ @Snipergirl You can sublime iodine by heating, because it melting point and boiling points are close, but technically it doesn't sublime at ambient pressure… you can find an intermediate temperature where you will obtain the liquid $\endgroup$
    – F'x
    Commented Sep 1, 2013 at 7:04
  • $\begingroup$ @Fx oh wow! Did not know that! there you go :) $\endgroup$
    – Tomcat
    Commented Sep 1, 2013 at 9:43

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