Some Typical Calculations for

Standard Gibbs Function for Formation of Aqueous Solute HCI 

We have discussed in some detail the various methods that can be used to obtain the standard Gibbs function of formation of a pure gaseous compound such as HCl(g). As many of its reactions are carried out in aqueous solution, it also is desirable to know AfGm for HCl(aq). 

We can write the following three equations, whose sum is equivalent to Equation (20.36)  

The activity of HCl in a 4-molal solution required for the AG i in Equation (20.39) was calculated from the mean activity coefficient, 1.762, taken from tables of Hamed and Owen [10], as follows  

Now we can obtain the standard Gibbs function change for Equations (20.36), because the sum of Equations (20.37) through (20.39) yields 

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