Can He Gas Be Compressed into a Quark Plasma State?

AI Thread Summary
Compressing helium gas in a thermally isolated tank will cause the temperature to rise due to the work done on the gas. It is unlikely that further compression will lead to a solid state, as the attractive forces may not be sufficient to induce a phase transition from gas to solid at room temperature and 1 atm. The temperature gradient is expected to rise linearly with pressure, as the work done remains constant while the number of molecules per unit pressure increases. If helium were compressed to the point of becoming quark plasma, it would likely result in extremely high temperatures and possibly an explosive event, similar to stellar collapses. The discussion also highlights that helium has a negative Joule-Thomson coefficient at normal temperatures, indicating it heats upon expansion and may cool upon compression until the coefficient changes.
fargoth
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ok, i have forgotten my thermodynamics, and need a confirmation for my thoughts here...if youd compress He gas by blowing more gas into a thermo-isolated tank, the tank would get hotter right?
and after compressing it enough the gas will become fluid (thats not a real phase transition, but you can't call it gas nor liquid after some density).

1) would you get a solid state after even more compression?
-my guess is no, because i can't see anything that would cause such a phase transition, i don't think the attractive powers will ever get strong enough if we started with He gas at room temprature and 1atm, as the temprature keeps rising when we compress it.

2) will there be a change of the temprature gradient as a function of pressure or will the temprature rise leniearly as a function of pressure?
-my guess is it'll rise linearly, because the work done for increasing the pressure is always the same for constant volume, but youd get less molecules inside the tank per unit pressure increase.

3) what would happen if youd compress it all enough to become "quark plasma" (like neutron star)?
- my guess is that it'll be VERY hot, it should make an explosion when it collapses like stars do, and we'll probably won't see it anymore, because light doesn't interact with it anymore.

am i right?
please regard all three guesses...

EDIT:
by the way, i kinda got carried away with this post, so the title is a bit misleading, no cooling here if I am right... so if any moderator is there, feel free to change the subject's name...
 
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There's actually some debate as to wether or not helium would be a solid at high pressure;

http://www.iop.org/EJ/article/0953-8984/16/10/L02/cm4_10_l02.html
 
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thanks for the reply,
so they don't know what happen's at low temprature and high pressure.
but I am not necessarily talking of low temprature, if my guesses are correct the system should be very hot...

anyway, i ran into something interesting here:
"This gas (He) has a negative Joule-Thomson coefficient at normal ambient temperatures, meaning it heats up when allowed to freely expand."

does that mean that on expansion it gets heated, and on compression it gets cold? (untill the coefficient changes its sign)?
 
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