Adiabiatic Process: q=0 & Work Done Path Function?

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Discussion Overview

The discussion revolves around the nature of work done in adiabatic processes, specifically addressing the relationship between internal energy, work, and the concept of path functions versus state functions. Participants explore the implications of these concepts in both reversible and irreversible adiabatic processes.

Discussion Character

  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants assert that in an adiabatic process, where q=0, the change in internal energy is equal to the work done, leading to the question of why work differs between reversible and irreversible processes.
  • It is noted that internal energy is a state function, which leads to the claim that work done in an adiabatic process should also be a state function, although this is challenged by the nature of the process.
  • One participant emphasizes that the assumption of thermodynamic equilibrium is crucial, stating that outside of equilibrium, the concept of a "path function" becomes ill-defined.
  • Another participant reiterates the initial question, clarifying that they meant to refer to state functions rather than path functions, and seeks further clarification on the differences in work done in reversible versus irreversible processes.

Areas of Agreement / Disagreement

Participants express differing views on the definitions and implications of path functions and state functions in the context of adiabatic processes, indicating that multiple competing views remain and the discussion is unresolved.

Contextual Notes

There are limitations regarding the assumptions made about thermodynamic equilibrium and the definitions of path and state functions, which are not fully resolved in the discussion.

Rachit Garg
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In an adiabiatic process q=0 so change in internal energy become equal to work. Since internal energy is path function so work done in an adiabiatic process should also be path function then why work done in adibiatic reversible and irreversible different?
 
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Rachit Garg said:
internal energy is path function so work done in an adiabiatic process should also be path function

This assumes that every state traversed by the process is a thermodynamic equilibrium state. Out of thermodynamic equilibrium, the concept of a "path function" is not well-defined.

Rachit Garg said:
why work done in adibiatic reversible and irreversible different?

Because in an irreversible process, the intermediate states are not in thermodynamic equilibrium.
 
By mistake i have wriitten that i want to say In an adiabiatic process q=0 so change in internal energy become equal to work. Since internal energy is state function so work done in an adiabiatic process should also be state function then why work done in adibiatic reversible and irreversible different?
 
Rachit Garg said:
By mistake i have wriitten that i want to say In an adiabiatic process q=0 so change in internal energy become equal to work. Since internal energy is state function so work done in an adiabiatic process should also be state function then why work done in adibiatic reversible and irreversible different?

This is basically the same question you asked in your OP, and I answered it in post #2. (My answer is still valid if you substitute "state function" for "path function".) Do you have questions about my answer?
 

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