Can Iron Exist as a Gas Without Becoming Plasma?

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CthlhuLies
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The way I understand plasma is that is almost a gas except some of the electrons of separated from the nuclei entirely making positively charged. Is there a temperature in which Iron is by definition a gas, and not a plasma?

Also, can something like a noble gas become a solid?
 
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CthlhuLies said:
Also, can something like a noble gas become a solid?

Sure. Neon, for instance turns solid at about 24.5 K.
 
dauto said:
Sure. Neon, for instance turns solid at about 24.5 K.

Would this have to be under pressure or could it be 24.5 kelvin in a vacuum and still be a solid?

Also nice job on the 700 posts :D
 
CthlhuLies said:
Would this have to be under pressure or could it be 24.5 kelvin in a vacuum and still be a solid?

Also nice job on the 700 posts :D

That's at standard pressure. Only helium does not turn solid at standard pressure. If memory serves, a minimum of 20 atmospheres is required (and extremely low temperatures) to produce solid helium
 
dauto said:
That's at standard pressure. Only helium does not turn solid at standard pressure. If memory serves, a minimum of 20 atmospheres is required (and extremely low temperatures) to produce solid helium
The critical pressure of helium is 2.24 atm., so the equilibrium vapor pressure at the solidification temperature is lower than this.

Chet
 
CthlhuLies said:
The way I understand plasma is that is almost a gas except some of the electrons of separated from the nuclei entirely making positively charged. Is there a temperature in which Iron is by definition a gas, and not a plasma?
There is no clear border between gas and plasma - if you increase the temperature, you just increase the fraction of ionized atoms.
The first ionization energy of iron is 8 eV and iron becomes a gas at ~3000K or ~1/4 eV, at this temperature the fraction of ionized atoms is low (but still existent).

Chestermiller said:
The critical pressure of helium is 2.24 atm., so the equilibrium vapor pressure at the solidification temperature is lower than this.
Where is the relation between the critical pressure (=gas/liquid related) and the solid phase?

Here is a phase diagram of helium
 
mfb said:
There is no clear border between gas and plasma - if you increase the temperature, you just increase the fraction of ionized atoms.
The first ionization energy of iron is 8 eV and iron becomes a gas at ~3000K or ~1/4 eV, at this temperature the fraction of ionized atoms is low (but still existent).

Where is the relation between the critical pressure (=gas/liquid related) and the solid phase?

Here is a phase diagram of helium
Yikes. I've never seen a phase diagram like this before. I guess you learn something new every day. Thanks.

Chet