Temperature Dependence of the Standard Electrode Potential

There might be a misinterpretation in calculating the standard electrode potential at an elevated temperatnre. The issue will be illustrated using an example. Let us assume we need to calculate of the following half-reaction 

Note that in the preceding equations, the absolute values of entropy and iso-baric heat capacity are used. As it is known from thermodynamics, the absolute values of Gibbs energy and enthalpy are not known, but the absolute values of their temperature and pressure derivatives are known. Also, we should keep in mind that the Gibbs energies and enthalpies of formation of all chemical elements in their reference state conventionally equal zero at any temperature. In addition, the absolute values of entropy, heat capacity, etc. (all other derivatives) of 

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