Ions, absolute properties mobility

FIGURE 5.9 Pairwise correlations between ion mass (or m/z), absolute mobility, and coefficients Oi and 02 for amino acid cations ( ) and anions (o). (From Shvartsburg, A.A., Mashkevich, S.V., Smith, R.D., J. Phys. Chem. A, 110, 2663, 2006.) The transport properties (in N2 gas) are from IMS and FAIMS experiments. No values of K for anions have been... 

The changes in the film material with the current density, field, and temperature at which the films are made (in dilute, aqueous solution) and the changes which occur on subsequent annealing at temperatures of up to 200 C or so, represent large proportional changes in the concentration of mobile ions, that is, according to the usual theory, in the concentration of defects (interstitial metal ions and anion and cation vacancies). However, the absolute variations in terms of numbers of defects are probably small. Thus the variations in properties, which are not directly functions of defect concentrations, such as refractive index and density, are of the order of 1 %— not large for ordinary formation conditions—whereas the variations in those properties, such as ionic conductivity, electronic conductivity, and rate of dissolution in which are directly dependent on the concentra-... 

A great difficulty when dealing with electrolytes is to ascribe individual properties to individual ions. Individual thermodynamic properties cannot be determined, only mean ion quantities being measurable. Interionic and ion-solvent interactions are so numerous and important in solution that, except in the most dilute cases, no ion may be regarded as behaving independently of others. On the other hand, there is no doubt that certain dynamic properties such as ion conductances, mobilities and transport numbers may be determined, although values for such properties are not absolute but vary with ion environment. 

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