Entropies in Thermodynamic Calculations

With tables of ion entropies available, it is possible to estimate a Gibbs function change without the necessity of carrying out an experiment or seeking specific experimental data. For example, without seeking data for the potential of calcium electrodes, it is possible to calculate the calcium electrode potential or the Gibbs function change in the reaction 

The Gibbs function for formation of NH4(aq) can be obtained from the following information  

Keep in mind that although a and 02 are both 1, they have not been defined on the basis of the same standard state. 

Given the following information for CO2 and its aqueous solutions, and using standard sources of reference for any other necessary information, calculate the standard Gibbs function of formation at 298.15 K for the CO3 ion. Henry s-law constant [see Equations (15.8) and (15.9)] for solubility in H2O = 29.5 for p in atmospheres and m2 in moles (kg H20).  

The solubility of pure solid glycine at 25°C in water is 3.33 moles (kg H20). The activity coefficient of glycine in such a saturated solution is 0.729. Data for the relative partial molar enthalpies of glycine in aqueous solution are tabulated in Exercise 15 of Chapter 18. Given AfG and 

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