Chemical potential of an ideal gas

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Discussion Overview

The discussion centers on the derivation of the chemical potential of an ideal gas, specifically the expression µ(T,V,N) = k_b T(a + 1 + ln(Nv_0/V)). Participants explore the conditions and assumptions necessary for this formulation, as well as alternative approaches to derive the chemical potential.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant asks how to show that the chemical potential of an ideal gas can be expressed in the proposed form.
  • Another participant argues that the derivation of the formula for µ requires additional assumptions beyond the ideal gas law (pV = NkT).
  • A different participant relates the expression for chemical potential to the Gibbs free energy and suggests that the terms in the formula correspond to internal energy and entropy, prompting a request for derivation of these components.
  • One participant speculates that Stirling's approximation may be relevant to the derivation of the entropy term in the expression.
  • Another participant asserts that the chemical potential should be derived using the definition involving entropy and suggests using the Sakur-Tetrode equation for this purpose.

Areas of Agreement / Disagreement

Participants express differing views on the assumptions required for deriving the chemical potential, with no consensus reached on the validity of the proposed formula or the methods suggested for its derivation.

Contextual Notes

There are unresolved assumptions regarding the internal energy and entropy of the ideal gas, as well as the applicability of different mathematical approaches to the derivation of the chemical potential.

chrisdk
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hi,
How can I show that the chemical potential of an ideal gas µ(T,V ) can be given by:
<br /> \mu(T , V , N )=k_{b}T\left(a+1+ln(\frac{Nv_{0}}{V})\right)<br />
 
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The only condition for an ideal gas is that it fulfills pV=NkT.
There are no restrictions to its internal energy and it doesn't even need to be extensive, so I don't think you cann show that formula for mu without further assumptions.
 
The Gibbs free energy is G = μN = U + PV -TS. It has three terms, and in your formula there are also three terms. It must be that they correspond: U = akT and S = -k ln(Nv0/V). Can you derive either of these?
 
Does it have to do something with Stirling's approximation (the latter one)? Concepts of statistical thermodynamics were never my strong side... :( Bill, can you help me out with this?
 
I don't know wtf u got in the OP but the way of deriving the chemical potential of an ideal gas is to use the definition μ= -T (∂S/∂N)|U,V

Use this on the Sakur-Tetrode equation. Use mathematica is you suck at differentiation.
 

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