Strong electrolytes in aqueous solutions

It is important to realise that whilst complete dissociation occurs with strong electrolytes in aqueous solution, this does not mean that the effective concentrations of the ions are identical with their molar concentrations in any solution of the electrolyte if this were the case the variation of the osmotic properties of the solution with dilution could not be accounted for. The variation of colligative, e.g. osmotic, properties with dilution is ascribed to changes in the activity of the ions these are dependent upon the electrical forces between the ions. Expressions for the variations of the activity or of related quantities, applicable to dilute solutions, have also been deduced by the Debye-Hiickel theory. Further consideration of the concept of activity follows in Section 2.5. 

The species appearing as strong electrolytes in aqueous solutions lose this property in low-permittivity solvents. The ion-pair formation converts them to a sort of weak electrolyte. In solvents of very low-permittivity (dioxan, benzene) even ion triplets and quadruplets are formed. 

Bromley, L. A., "Thermodynamic Properties of Strong Electrolytes in Aqueous Solutions," AIChE J., 1973, 19, 313. 

Hamer, W. J. "Theoretical Mean Activity Coefficients of Strong Electrolytes in Aqueous Solution from 0 to 100 C" NSRDS-NBS 24, U.S. Department of Commerce, National Bureau of Standards, December 1968. 

As remarked in Sidebar 3.11, soluble salts MA (M = cation, A = anion) often behave as strong electrolytes in aqueous solutions, dissociating completely into ionic species as expressed by... 

A properly balanced chemical equation shows all the information we have just discussed. Soluble salts and strong electrolytes in aqueous solution are always written in ionic form—for example, Na+ + n0 NaCl) or H+ 0r H30+)... 

Because salts are generally strong electrolytes in aqueous solution, we can write the neutralization reaction of a strong acid with a strong base as an ionic equation ... 

Bromley, L.A. 1973. Thermodynamic properties of strong electrolytes in aqueous solutions. AIChE J. 19 (2) 313-320. 

Meissner Tester, "Activity Coefficients of Strong Electrolytes in Aqueous Solutions", I EC Process Design and Development, vol 11, p 128, (1972)... 

A strong electrolyte in aqueous solution may be represented as separate ions because the ions of each type are free to move about independently of the ions of the other type. However, an ionic solid that is not dissolved in water is not written as separate ions the oppositely charged ions in the solid lattice of an ionic compound are not independent of each other (Figure 9.2). 

According to the Debye-Hilckel theory (Chapter XVII), A should bo 0.375 for all uni-univalent strong electrolytes in aqueous solution at 0 C x should be exactly 0.5 for all strong electrolytes. 

Sutherland went a step further by expressing the opinion that all strong electrolytes in aqueous solution were completely dissociated into ions. N. Bjerrum arrived at similar conclusions on the basis of experimental investigations. The mathematical treatment (cf. Milner ) of the problem of interionic forces proved to be extremely difficult, and therefore Bjerrum had to be satisfied temporarily with expressing the effects produced by the electrostatic influence of ions by means of empirical deviation coefficients. These coefficients gave the ratio of the observed value to that which should be obtained in the absence of interionic forces. He proposed the three following factors ... 

The Ionisation and Activity of Strong Electrolytes in Aqueous Solution... 

KEN] Kenttamaa, J., A cryoscopic method of studying the incomplete dissociation of strong electrolytes in aqueous solutions, Suom. Kemistil. B, 29B, (1956), 59-64. Cited on pages 181, 182, 183, 187,284,288. 

Meissner, H.P. and Tester, J.W. (1972) Activity coefficients of strong electrolytes in aqueous solution. Industrial and Engineering Chemistry, Process Design and Development, 11, 128-133. 

Femandez-Prini R (1969) Conductance of electrolyte solutions. Modified expression for its concentration dependence. Trans Faraday Soc 65 3311-3313 Frank HS, Robinson AL (1940) The entropy of dilution of strong electrolytes in aqueous solutions. J Chem Phys 8 933-938... 

Another variation of crystallization out of a solution, is separation by adding a salt (chemical precipitation). Nonelectrolytes or weak electrolytes are replaced by strong electrolytes in aqueous solutions [7.1, 7.18]. 

Bromamine - B, like chloramine - T and chloramine - B, behaves as a strong electrolyte in aqueous solutions forming different species [7-9] ... 

Strong Electrolytes in Aqueous Solution - Effect of Temperature", AIChE J., 18, 661 (1972)... 

W. J. Hamer, Theoretical Mean Activity Coefficients of Strong Electrolytes in Aqueous Solutions from 0 to 100°C, NBS No. 24, U. S. Government Printing Office, Washington, D. C., 1968. 

At the Prague Institute of Chemical Technology, F. Jirsa studied anodic oxidation of gold [15] later he published an important paper about silver electrode for a silver-iron battery [16], Jaroslav Chloupek (1899-1975), partly with V. Danes (1907-1980) and B. Danesova, studied the electrode potential in solutions of mixed manganese salts [17], the solubility and activity coefficient of Ag2S04 in some solutions [18], the ions and deviations from the approximation of Debye-Hiickel theory [19], the liquid potentials [20], and the anomalous valency effect of strong electrolytes in aqueous solution [21]. 

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