A question about terminology of phase state & criticality

AI Thread Summary
The discussion centers on the terminology related to phase states and criticality, specifically regarding supercritical fluids and subcritical conditions. A supercritical fluid exists when both temperature and pressure exceed the critical point, exhibiting properties of both gas and liquid. The terms subcritical gas and liquid refer to states where both temperature and pressure are below the critical point, with subcritical gas also referred to as vapor. The inquiry raises questions about gases at higher temperatures but lower pressures, and liquids at higher pressures but lower temperatures than the critical point, suggesting a need for specific terminology for these states. Ultimately, participants conclude that these conditions may simply be classified as normal gas or liquid without requiring additional terminology.
swampwiz
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I'm looking at the diagram (Figure 1) at

http://en.wikipedia.org/wiki/Supercritical_fluid

I get that the region in which both the temperature & pressure are higher than the critical point is called a supercritical fluid, which really means it is both a gas & a liquid, thermodynamically speaking.

And as I understand it, the term subcritical gas or liquid is for the region in which the temperature & pressure are both less than the critical point - with the subcritical gas also termed a vapor here.

But what about a gas that is a higher temperature but lower pressure, or a liquid at a higher pressure, but lower temperature, than the critical point. It seems that there should be some term for this that is something like a "saddle" state. I don't think the term supercritical should be used, but something with critical should be.

Any idea what the terminology of this is?
 
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a gas that is a higher temperature but lower pressure...

Isn't it just normal gas? How does it differ?

a liquid at a higher pressure, but lower temperature,

Isn't it just a normal liquid? Ditto?
 
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