Gibbs function solute

Note that eq. (3.16) involves the Helmholtz function, A, rather than the Gibbs function G, but the difference between A A and AG is negligible in solutions and we will use AG in this book. 

Thermodynamic stability. Let us consider a liquid binary mixture of two species, a and b, crystallizing to a solid solution. Let G be the free enthalpy (Gibbs) function of each phase, either solid or liquid. Calculate the change AG in molar free enthalpy when a liquid of molar composition XUqb crystallizes to a solid of molar composition... 

Thus, the change in the Gibbs function for the transfer of one mole of the solute from a molality m2 to a molality m is... 

Therefore the state in which the solute has a partial molar Gibbs function of p.2 can be found from the following limit, because 72 approaches unity as m2 approaches zero ... 

Although the description of deviations from ideality in terms of the excess Gibbs function gives us one quantity instead of the two activity coefficients of the two components of a binary solution, we still need to calculate the activity coefficients first, as observed in Equation (16.57). 

Deviations from ideality in real solutions have been discussed in some detail to provide an experimental and theoretical basis for precise calculations of changes in the Gibbs function for transformations involving solutions. We shall continue our discussions of the principles of chemical thermodynamics with a consideration of some typical calculations of changes in Gibbs function in real solutions. 

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). 

Solute Very Soluble Sodium Chloride. As the standard Gibbs function for formation of NaCl(s) is available [11], the AfGm 29s for NaCl(aq) can be obtained... 

For the Gibbs function change in Equation (20.61), 02 of the undissociated species of succinic acid in the saturated solution is obtained as follows ... 

CHANGES IN GIBBS FUNCTION FOR PROCESSES IN SOLUTIONS For this reaction... 

The preceding examples illustrate some methods that can be used to combine data for the Gibbs functions for pure phases with information on the Gibbs function for constituents of a solution to calculate changes in the Gibbs function for chemical... 

To better understand the complexity of situation, it is useful to apply some thermodynamic considerations. The separation process is governed by the change of the Gibbs function due to transfer of solute molecules between the mobile and the stationary phase. One can write... 

Gibbs functions for a real salt solution and the corresponding ideal salt solution containing m2 moles of salt in a kilogram of solvent. GE can be calculated for many aqueous salt solutions from published values of 0 and y . In the same way, the corresponding excess enthalpy HE can be defined and this equals the apparent partial molar enthalpy. Thus the properties of salt solutions can be examined in plots of GE, HE, and T SE against m2, where SE is the... 

Considerable information concerning structural effects on aqueous salt solutions has been provided by studies of the properties of mixed solutions (Anderson and Wood, 1973). In a mixed salt solution prepared by mixing YAm moles of a salt MX (molality m) with Yhm moles of a salt NX (molality m) to yield m moles of mixture in 1 kg of solvent, if W is the weight of solvent, the excess Gibbs function of mixing Am GE is given by (19) where GE is the excess function for... 

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