Thermodynamic Properties from the Partition Function

The relationships between the thermodynamic properties of a system and its partition function Q are developed very eloquently by Denbigh (1981, p.345). We present here the final results only  

S = klnQ + V V,comp. Finally, since from thermodynamics (16.7.3) 

We conclude, therefore, that if the partition function Q of a constant composition fluid is known as a function of temperature and volume, all thermodynamic properties of the system can be determined. This is demonstrated next with the case of an ideal gas. 

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