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Re: CO2 phase term

Aquatic Plants Digest wrote:
> From: ChuckW7160 at aol_com
> Subject: re: CO2 phase term
> Jeff-
> I believe the term you are looking for is sublime.  If i'm remembering right
> when a substance goes directly from solid to gas, or gas to solid skiping the
> liquid state it is said to sublime. can't exactly call the act of dry ice
> going straight to gas melting :) that would imply a liquid state. 

Right.  And the diagram of a substance's phases includes both pressure
and temperature as the axes.  So at some pressures (higher than
standard) CO2 does exist as a liquid - as in your compressed cylinder. 
What I don't recall from basic chemistry is if all substances have a
sublimation point at some low pressure.  Also, what governs how much of
a substance (snow for instance) melts and how much sublimes if both are happening?

Christopher L. Weeks