Can you explain the 2nd law of thermodynamics using closed isolated systems?

AI Thread Summary
The discussion centers on the confusion surrounding the concepts of isolated and open systems in relation to the second law of thermodynamics. Participants clarify that an "isolated open system" is a contradiction, as open systems allow energy and material exchange, while isolated systems do not. The second law pertains to entropy in closed isolated systems, which contain multiple interacting particle species. Understanding this law requires recognizing that the number of particles can change, necessitating a discussion of chemical potentials to achieve equilibrium. The conversation emphasizes the importance of precise terminology in thermodynamics.
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can someone give me an example of isolated open systems ,which can allow me to understand 2nd law of thermodynamics?,bcoz i don't think there's anything called open system and that too in isolation
 
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What do you mean by an 'isolated open system'? The only meaning I've seen attached to 'open system' is that energy and material can be exchanged with its surroundings, which obviously means it isn't isolated...
 
I think you're right. To me, "isolated open system" is like saying "hot ice"; it's a contradiction. But what exactly don't you understand about the 2nd Law? If it's about the definition of entropy and what it is, you're definitely not the first to have questions.
 
The term is poorly chosen, but what it's referring to is an isolated system containing more than one species of particles that can interact and turn into one another. It's 'open' in the sense that the Nk's are not constant, and therefore to discuss equilibrium you need to talk about the chemical potentials.
 
Bill_K said:
The term is poorly chosen, but what it's referring to is an isolated system containing more than one species of particles that can interact and turn into one another. It's 'open' in the sense that the Nk's are not constant, and therefore to discuss equilibrium you need to talk about the chemical potentials.

sorry,typing error and thought mixing error,i mean close isolated systems
 
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