How Does Maxwell's Demon Relate to Entropy and Gas Separation?

AI Thread Summary
Maxwell's Demon illustrates concepts related to entropy and gas separation, particularly in the context of the Second Law of Thermodynamics. In a hypothetical scenario where a gas mixture of hydrogen and argon is released on a planet without an atmosphere, the lighter hydrogen escapes while the heavier argon remains, leading to gas separation. Despite this separation, the overall entropy of the system increases because both gases expand and occupy more volume. The discussion clarifies that there is no paradox in this situation, and understanding entropy will become clearer with further study of thermodynamics. The relationship between gas behavior and entropy is crucial in grasping these thermodynamic principles.
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Hi,
I've not covered yet the Second's Law of thermodynamics so I don't understand it well. A friend of mine talked to me about Maxwell's demon and now I have the following question :
Imagine a planet such that its escape velocity is about Earth's one, but without any atmosphere. Now imagine I have a composed gas (hydrogen+argon) and I free it at ground level. After some time all the hydrogen would leave out the planet and the argon would remain on the planet. So without any intervention the 2 gases are separated. How has the entropy increased?
Thank you.
 
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There's no conflict here- both gases expand, and the entropy of the system (planet+ gases) is proportional to the volume occupied.
 
Andy Resnick said:
There's no conflict here- both gases expand, and the entropy of the system (planet+ gases) is proportional to the volume occupied.

Ah ok!
I thought that by separating the 2 gases the entropy would have decreased. Anyway I'll be soon studying the second law of thermodynamics so I guess I will understand what is entropy and understand better the example I gave here.
Thank you for the answer. (so there's no ambiguity, no paradox nor anything wrong with the situation described above).
 
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