The Thermodynamics of Ions

If the reversible element is a metal or hydrogen, which is in equilibrium with positive ions (cations), the reaction occurring at the electrode when it forms part of a cell may be formulated as 

Electrodes of the second type consist of a metal and a sparingly soluble salt of this metal in contact with a solution of a soluble saU of the same anion. An example of this form of electrode consists of silver, solid silver chloride and a solution of a soluble chloride, e.g., hydrochloric acid, via., 

The reaction in this electrode consists, first, of the passage of silver ions into solution, or the reverse, i.e., 

Electrodes of this kind haA e been made Avith other similar halides, e.g., silver bromide and iodide, and mercurous chloride and bromide, and also with various sparingly soluble sulfates, oxalates, etc. 

The third type of reversible electrode consists of an inert metals e.g., gold or platinum, immersed in a solution containing both oxidized and reduced states 

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The thermodynamics of ion backspillover from the solid electrolyte to the gas exposed electrode surface have been discussed in section 3.4.3 and also... 

This point was raised by K. L. Babcock, L. E. Davis, and R. Overstreet, Ionic activities in ion-exchange systems, Soil Sci. 72 253 (1951). The problem of the Reference State for ion exchangers is reviewed by L. W. Holm, On the thermodynamics of ion exchange equilibria. I. The thermodynamical equilibrium in relation to the reference states and components, Aark. Kem. 10 151 (1956). 

Several workers have reported thermochemical data for ion exchange in resins but a relatively recent extensive study has been given by Boyd, some of whose results are presented in Tables 5.3a-d. These and similar studies offer a means of attempting to unify the thermodynamics of ion exchange with the exchange mechanism as postulated by various molecular theories. 

Record, T., M. Olmsted and C. Anderson. (1990). Theoretical studies of the thermodynamics of ion interaction with DNA. Theoretical Biochemistry and Molecular Biophysics. Adenine Press. 

The dynamic character of polymers such as Nafion in terms of solvent swelling can have a marked influence on the thermodynamics of ion exchange processes. 

In conclusion the attention of the reader is drawn to the elegant and detailed examination of the thermodynamics of ion exchange in clinoptilolite from Death Valley Junction, California, carried out by Pabalan [71], and by Pabalan and Bertelti [72]. 

In considering the thermodynamics of ion solvation, two equilibria of great importance are... 

Ion adsorption to mineral surfaces is an important phenomenon in many industrial applications as well as in the study of the natural environment. Ion exchange on constant charge minerals was initially the ion adsorption process that was studied most intensively both experimentally and theoretically. The success in this field was due to a combination of efforts. Mineralogists andcrystallographers unravelled the detailed structure of the minerals after 1930, theoretical chemists developed the well known double layer theories around 1910-1925, and the thermodynamics of ion exchange was formulated around 1950. Colloid and soil chemists in the mean time developed the various applications of this work and it became widely used by practitioners. 

Having established in the previous sections the thermodynamics of ion hydration, attention may now be turned to the thermodynamics of the solvation of the ions in nonaqueous solvents. As mentioned before, it is expedient to deal not with the solvation process of ions in the ideal gas phase going into the nonaqneous solvents, but to deal with their transfer from water (W) as the sonrce solvent to the nonaqueous solvent as the target solvent (S) ... 

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