Contribution to the Gibbs Free Energy for a Linear Diatomic Molecule

Vibrational Contribution to the Gibbs Free Energy For a Linear Diatomic Molecule From equations (10.84) and (10.101) 

Substitution of Zm.yib from the second equation into the first gives 

we note that the RT term is not added in changing from (Am - Uo.m) to (Gm - H0.m). This term is added only in the translational contribution. 

Calculation of Thermodynamic Properties We note that the translational contributions to the thermodynamic properties depend on the mass or molecular weight of the molecule, the rotational contributions on the moments of inertia, the vibrational contributions on the fundamental vibrational frequencies, and the electronic contributions on the energies and statistical weight factors for the electronic states. With the aid of this information, as summarized in Tables 10.1 to 10.3 for a number of molecules, and the thermodynamic relationships summarized in Table 10.4, we can calculate a 

Solution Ar is a monatomic gas with Zm.eica = 1. The translational contribution is the only one we need to consider. For Ar, M = 0.039948 kg-mol-1. We want the standard state entropy when p = 1.000 x 105 Pa. Substituting into the equation in Table 10.4 gives 

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