Partial molar functions of component

The partial molar functions of the component B can be calculated using the Gibbs-Duhem equation. The Gibbs-Duhem equation for any partial molar function Z (Z equal to AG, AS, AH, etc.) has the general form 

Apphed to the Gibbs function of a binary alloy one obtains 

The integration of these equations gives the partial molar functions of component B. For the integration the integration constants must be known. Because the potential difference was measured between the alloy and the pure metal, the partial molar functions are relative values referring to the pure metal as a reference state. Therefore, integration is carried out between Xg=1, x = 0 and Xg, and x = 1 Xg. 

Integrating these equations, one sometimes extrapolates to also 

In a similar manner one can reduce AG and A5 to the non-ideal part with the equations 

---

This procedure provides a second way to obtain partial molar functions of component B. The partial molar functions of A, AZ, are known from potential measurements. One can then calculate the partial molar functions of component B from Aj, Z subtracting the partial molar function AZ according to the equation... 

---