Fundamental equation and state equations of the ideal gas

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SUMMARY

The discussion focuses on deriving the fundamental equation of a monoatomic ideal gas using the Helmholtz potential, enthalpy, and Gibbs function representations. The fundamental equation is given as S = (NS0/N0) + NR ln[(U/U0)^(3/2) (V/V0) (N/N0)^(-5/2)]. The participant successfully formulates the Helmholtz free energy as F(T,V,N) = U - TS and expresses U in terms of temperature and particle number. The equations of state are derived through differentiation of the fundamental equation.

PREREQUISITES
  • Understanding of thermodynamic potentials, specifically Helmholtz free energy.
  • Familiarity with the ideal gas law (PV = NRT).
  • Knowledge of statistical mechanics concepts related to entropy and energy distributions.
  • Ability to perform differentiation in the context of thermodynamic equations.
NEXT STEPS
  • Study the derivation of the Helmholtz free energy in thermodynamics.
  • Learn about the Gibbs free energy and its applications in phase equilibria.
  • Explore the statistical mechanics foundations of entropy and its relation to thermodynamic functions.
  • Investigate the implications of the ideal gas law in various thermodynamic processes.
USEFUL FOR

Students and professionals in thermodynamics, particularly those studying ideal gas behavior and thermodynamic potentials. This discussion is beneficial for anyone looking to deepen their understanding of the fundamental equations governing monoatomic ideal gases.

fluidistic
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Homework Statement


Find the fundamental equation of a monoatomic ideal gas in the Helmholtz potential representation, in the enthalpy representation, and in the Gibbs function representation. Assume the fundamental equation [itex]S= \frac{NS_0}{N_0} +NR \ln \left [ \left ( \frac {U}{U_0} \right ) ^{3/2} \left ( \frac{V}{V_0} \right ) \left ( \frac {N}{N_0} \right ) ^{-5/2} \right ][/itex]. In each case find the equations of state by differentiation of the fundamental equation.


Homework Equations


Helmholtz: F=U-TS. But F(T,V,N)
PV=NRT.
[itex]U=\frac{3NRT}{2}[/itex].


The Attempt at a Solution


I first deal with Helmholtz.
If I understand well, I must get F(T,V,N)=U-TS. I already have U in terms of T and N. The last task is therefore to get S in terms of T,V and N which seems easily made by using the given fundamental equation.
It gives me [itex]F(T,V,N)=\frac {3NRT}{2}-T \{ NK_1 +NR \ln \left [ \left ( \frac{V}{V_0} \right ) \left ( NTK_2 \right ) ^{3/2} \left ( \frac{N}{N_0} \right ) ^{-5/2} \right ] \}[/itex].
So far I wonder if my approach is a right one. Is it ok so far?
 
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I just got a reminder that this question went unanswered.
Tbh, I have no clue. Well... maybe if I think hard about it...
Erm... @fluidistic, can you perhaps write an answer by now?
 

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