Gibbs free energy carbon monoxide

Determine the equilibrium composition that is achieved at 300 bar and 700 K when the initial mole ratio of hydrogen to carbon monoxide is 2. You may use standard enthalpy and Gibbs free energy of formation data. For purposes of this problem you should not neglect the variation of the standard heat of reaction with temperature. You may assume ideal solution behavior but not ideal gas behavior. You may also use a generalized fugacity coefficient chart based on the principle of corresponding states as well as the heat capacity data listed below. 

Figure 10.22 Gibbs free energy changes (AC -q) per CO for the adsorption of carbon monoxide on Rh (3,l) cluster as a function of CO coverage (SATP, P = lbar, 7 = 298.15 K). (Reproduced with permission from Ref. [52]).

However, we also noted that in the case of hydrogen the absolute value of the Gibbs free energy decreases with temperatnre. It is the same for carbon monoxide, and so we can say that for all practical fuels this is so. It is impractical to operate a fuel cell at below ambient temperature, and so the highest possible efficiency limit will occur at ambient temperature, Ta. At this temperature the Gibbs free energy is maximum and is equal to AGt. So, in practice, we can refine our formula for the maximum efficiency to... 

Figure 97. The change in Gibb s free energy for the reduction of titanium oxides by carbon monoxide at 0.1 mbar total pressure.

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