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Debye-Huckel laws extended

Log Yj may be evaluated with extended Debye-Huckel law, but for most purposes, it is small and can be neglected, so that... [Pg.146]

Under what conditions does the extended Debye-Huckel law, equation 8.52, become the Debye-Hiickel limiting law ... [Pg.258]

If the ion radius, a, is put equal to zero in the extended Debye-Huckel law the equation repiesenting the simple Oebye-Huckel limiting law is regained. [Pg.48]

The Debye-Huckel Theory The Finite-Ion-Size Model. If the approximation of the point charge is removed, the extended form of the Debye-Huckel law is obtained ... [Pg.70]

Table 3.4 lists some activity coefficients as calculated from the extended Debye-Huckel limiting law for various values of /. In dilute solutions, such calculated values agree well with experimental data for mean activity coefficients of simple electrolytes. At higher concentrations, the Davies equation usually represents the experimental data better. [Pg.103]

Approximately the same result would be obtained from the extended Debye-Huckel limiting law (equation 1, Table 3.3) p"H = —log [H ] + 0.113 = 3.II3. [Pg.104]

A comparison of the calculated activity coefficients using the limiting law (4.32). the extended Debye-HUckel (4.34) and the HUckel equation (4.36) for sodium chloride at 26 Celsius can be found in figures 4.1 and 4.2. Also plotted are experimental values of the molal activity coefficient as published by Robinson and Stokes (5). The value used for a is 4.0 and. as suggested by Robinson and Stokes, C =. 055 l.roole . [Pg.56]

Rg. 2.7 Experimental activity coefficients ( ) and their ionic strength dependence shown schematically. DHL = Oebye-Huckel limiting law EOHL = Extended Debye-HQckel law RS s Robinson and Stokes equation. [Pg.47]

Figure 7.8 Comparison of experimental ln7 for 1 1, 2 1, and 2 2 electrolytes. The symbols indicate the experimental results, with representing HC1 (z+ = 1, z = — 1) representing SrC ( + = 2, r = — 1) and A representing ZnS04 (z+ = 2, z = -2). The lines are the Debye-Huckel predictions, with the solid line giving the prediction for (z+ = 1, z = -1) the dashed line for (z+ = 2, r = -1) and the dashed-dotted line for (z+= 2, z =-2). In (a), In 7- calculated from the limiting law [equation (7.45)] is shown graphed against I 2. In (b). In 7- calculated from the extended form [equation (7.43)] is shown graphed against 7m2. Figure 7.8 Comparison of experimental ln7 for 1 1, 2 1, and 2 2 electrolytes. The symbols indicate the experimental results, with representing HC1 (z+ = 1, z = — 1) representing SrC ( + = 2, r = — 1) and A representing ZnS04 (z+ = 2, z = -2). The lines are the Debye-Huckel predictions, with the solid line giving the prediction for (z+ = 1, z = -1) the dashed line for (z+ = 2, r = -1) and the dashed-dotted line for (z+= 2, z =-2). In (a), In 7- calculated from the limiting law [equation (7.45)] is shown graphed against I 2. In (b). In 7- calculated from the extended form [equation (7.43)] is shown graphed against 7m2.
For solutions that are more concentrated (i.e. for ionic strengths in the range 10 < I (mol dm ) < 10 ), we employ the Debye-Huckel extended law as follows ... [Pg.50]

Sulfuric acid is a 2 1 electrolyte, and so (by using the data in Table 3.1) the ionic strengthlis three times the concentration, i.e.l = 0.03 moldm f Next, from the Debye-Huckel extended law equation (3.15), we can obtain the mean ionic activity coefficient y as follows ... [Pg.52]

Electrolytes for which the concentration is less than lO Mcan usually be dealt with by the Debye-Huckel limiting law. Utilize the Debye-Huckel theory extended by allowance for ion size and also for removal of some of the active solvent into the ion s primary solvation shell to calculate the activity coefficient of 5 M NaCland 1M LaClj solutions (neglecting ion association or complexing). Take the total hydration number at the 5 M solution as 3 and at the 1 M solution as 5. Take r,- as 320 pm. [Pg.351]

What are the Debye-Huckel limiting law and the extended Debye-Hiickel equation and under what general conditions can they be used to compute ion activity coefficients Discuss the meaning and use of the ion size parameter in the Debye-Hiickel equation. How is it related to the ionic potential ... [Pg.615]

When concentrations are not low enough for molalities to be used, activity coefficients can be estimated from the Debye-Huckel limiting law or its extended form which read as... [Pg.1]

Repeat Illustration 15.1-6 for the dissociation of acetic acid in the presence of sodium chloride using the simple Debye-Huckel limiting law (instead of the extended version used in the illustration) and compare the results. [Pg.909]

We shall just mention here that the simple association theory may be extended by considering the interactions between defects in solution in a medium with dielectric constant a [14]. This is analogous to the Debye-Huckel theory of electrolytic solutions. As a result, the mole fractions of charged point defects of sort i in the mass action laws have to be replaced by their corresponding activities which according to Debye-Huckel are of the form... [Pg.47]

It is possible to understand why solutions of electrolytes do not behave in an ideal manner in terms of both the coulombic attraction on ions which serves to constrain their movement and the thermal agitation which counteracts this restraint. Debye and Huckel developed a theory in which electrostatic forces shaping the behavior of the ions in solution as well as their finite radii formed a basis from which expressions for the activity coefficient of an ion could be derived. One of the simpler usable equations they developed, referred to as the Extended Limiting Law, gives the activity coefficient, y, of an ion i, having a charge Zj in a solution of ionic strength I. [Pg.41]

In the application to strong electrolytes serious doubt exists whether the application of the complete cq. (40) is permissible because it implies certain internal inconsistencies which have been analys ed most extensively by Kirkwood But Casimir extending Kirkwood s analysis has shown that these inconsistencies do not arise (remain very small) when the complete eq. (40) is applied to the double layer on a large plane interface or on a large particle if the electrolytic concentrations in the whole system remain so small that in the bulk of the solution the limiting laws of Debye and Huckel form a reasonable approximation. [Pg.129]


See other pages where Debye-Huckel laws extended is mentioned: [Pg.466]    [Pg.48]    [Pg.48]    [Pg.26]    [Pg.26]    [Pg.466]    [Pg.48]    [Pg.48]    [Pg.26]    [Pg.26]    [Pg.78]    [Pg.43]   
See also in sourсe #XX -- [ Pg.186 ]

See also in sourсe #XX -- [ Pg.48 ]




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