Activity coefficient assumptions in the determination of association constants. VII. Explicit assumptions in the analysis of solubility and absorbance measurements on thallium(I) chloride and bromide

1972 ◽  
Vol 25 (2) ◽  
pp. 317 ◽  
Author(s):  
CY Chan ◽  
MH Panckhurst
Keyword(s):  
Activity Coefficient ◽  
Interaction Coefficient ◽  
Association Constants ◽  
Halide Ions ◽  
Ionic Interaction ◽  
Interaction Coefficients ◽  
Ionic Activity ◽  
Common Ion ◽  
Absorbance Data

In an attempt to resolve discrepancies between association constants obtained from solubility and absorbance measurements for thallium(1) chloride and bromide the explicit assumptions used in the various analyses have been considered in detail. It is shown that the discrepancies can be accounted for in part by considering the activity coefficient of the complex TlCl or TIBr, and, more importantly, by allowing for the presence of small amounts of higher complexes in analysing absorbance data. It is also shown, in determining association constants using a specific ionic activity coefficient expression, that uncertainties in some interaction coefficients reduce the usefulness of our solubility measurements in non-common ion salts. In particular, it is concluded, using the specific ionic interaction coefficient expression, that association constants can at present only be arrived at from solubility measurements by specifying arbitrary interaction coefficients for thallium(1) and halide ions; and to obtain association constants using a non-specific ionic activity coefficient expression it is necessary to assume unnecessarily arbitrary subsidiary association reactions as well as an arbitrary value for the activity coefficient parameter B.

Activity coefficient assumptions in the determination of association constants. VI. Association of thallium(I) bromide from absorbance measurements

1972 ◽  
Vol 25 (2) ◽  
pp. 311 ◽  
Author(s):  
CY Chan ◽  
MH Panckhurst
Keyword(s):  
Activity Coefficient ◽  
Aqueous Solutions ◽  
Association Constants ◽  
Experimental Results ◽  
Ionic Activity ◽  
Optical Absorbance ◽  
Different Types ◽  
Reasonable Description

Measurements are reported of the optical absorbance of aqueous solutions of thallium(I) bromide in mixture with other electrolytes a t 25°. These measurements are similar to those previously reported1 for thallium(I) chloride and are used in conjunction with two different types of ionic activity coefficient expressions to investigate association of thallium(I) bromide. Both types of expression give a reasonable description of the experimental results but there is the same disagreement with the analysis of solubility measurements found for thallium(1) chloride.

scholarly journals Experimental determination of activity interaction coefficients of components in Si-B-Fe and Si-B-Al ternary systems at 1723 K

2020 ◽  
Vol 56 (2) ◽  
pp. 153-160
Author(s):  
F. Yang ◽  
Y.-Q. Zhou ◽  
J.-J. Wu ◽  
W.-H. Ma ◽  
Y. Lei
Keyword(s):  
Experimental Determination ◽  
Ternary Systems ◽  
Interaction Coefficient ◽  
Boron Removal ◽  
Interaction Coefficients ◽  
Concentration Method ◽  
Equilibrium Concentrations ◽  
Silicon Materials ◽  
Determination Of Activity

The interactions among impurity components in Si-based solution are the important thermodynamic parameters for the purification of silicon materials. A ?same concentration? method was used to determine the activity interaction coefficients of Fe to B and Al to B in the silicon solution. Fe and Al were respectively dissolved into the binary Si-B solution at 1723 K with the holding time of 5 h, 7 h, 9 h, and 11 h. The equilibrium concentrations of Fe, B in the Si-B-Fe system and Al, B in the Si-B-Al system were determined. The interaction coefficients of Fe to B and Al to B were obtained by fitting the solubility data of B, Fe, and Al. The solubility relationships between B and [%Fe], and between B and [%Al] were obtained, respectively. It was found by the SEM and EPMA pictures of the samples that the third component Fe or Al added to the binary Si-B solution was alloyed, which verifies the accuracy of the experimental determination results. The significance of the activity interaction coefficient of B on boron removal from industrial silicon was analyzed.

Activity coefficient assumptions m the determination of the association constant of thallons chloride. II. Effect of interactions between freeions

1966 ◽  
Vol 19 (6) ◽  
pp. 915 ◽  
Author(s):  
JB Macaskill ◽  
MH Panckhurst
Keyword(s):  
Sodium Chloride ◽  
Activity Coefficient ◽  
Association Constant ◽  
Sodium Perchlorate ◽  
Barium Chloride ◽  
Specific Interactions ◽  
Ionic Activity ◽  
Caesium Chloride ◽  
Free Ions

The solubility of thallous chloride has been measured in solutions of hydrochloric acid, caesium chloride, caesium perchlorate, barium chloride, and in various mixtures of sodium chloride and sodium perchlorate. These measurements are analysed to give the association constant for thallous chloride, paying particular attention to ionic activity coefficient formulae. It is shown that an activity coefficient expression which assumes no specific interactions between free ions is unsatisfactory in contrast to an expression which assumes such interactions. The consequences of this are discussed.

Activity coefficient assumptions in the determination of association constants. V. Association of thallium(I) bromide from solubility measurements

1969 ◽  
Vol 22 (5) ◽  
pp. 911 ◽  
Author(s):  
CW Childs ◽  
MH Panckhurst
Keyword(s):  
Activity Coefficient ◽  
Sodium Acetate ◽  
Specific Interaction ◽  
Sodium Perchlorate ◽  
Potassium Bromide ◽  
Association Constants ◽  
Sodium Bromide ◽  
Specific Interactions ◽  
Free Ions

Measurements are reported of the solubility of thallium(I) bromide in aqueous solutions of potassium bromide, sodium perchlorate, barium bromide, and of mixtures of sodium bromide and sodium perchlorate and of sodium bromide and sodium acetate at 25�. The measurements are used to test the merits of two types of ionic activity coefficient expressions, one assuming specific interactions between free ions and the other not. It is shown that neither expression can describe our results adequately, in contrast to previous solubility results with thallium(I) chloride for which the specific interaction expression was adequate.

Specific ionic interactions and solubility activity product of caesium perrhenate at 298.10 K

1978 ◽  
Vol 31 (7) ◽  
pp. 1411 ◽  
Author(s):  
C Chan ◽  
KH Khoo ◽  
MH Panckhurst
Keyword(s):  
Activity Coefficient ◽  
Aqueous Solutions ◽  
Specific Interaction ◽  
The Other ◽  
Interaction Parameters ◽  
Ionic Interactions ◽  
Aqueous Mixtures ◽  
Ionic Interaction ◽  
Ionic Activity ◽  
Activity Product

The solubilities of caesium perrhenate in aqueous CsCl, NaCl, KCl and KReO4 solutions at 298.10 K are reported. The solubility activity product for CsReO4 was determined by using extrapolation functions involving two different mean ionic activity coefficient expressions and the results were compared; the total ionic strengths of all the saturated perrhenate solutions were less than 0.1 mol dm-3. One of these expressions used is that proposed recently by Panckhurst and Macaskill1,2 which is an extension of Guggenheim's approach,3,4 specific ionic interactions in aqueous solutions being explicitly taken into account. Its use led to more consistent values for the solubility activity product for CsReO4 than those obtained with the other expression which does not incorporate specific interaction parameters. Values of specific ionic interaction parameters for caesium, potassium and sodium perrhenates in dilute aqueous mixtures with CsCl, KCl, KReO4, KI or NaCl are also reported.

Octahedral cobalt(III) complexes in dipolar aprotic solvents. VI. Spectrophotometric determination of ion association of halide ions with cis-chlorodimethylformamidebisethylenediaminecobalt(III) ion and cis-chlorobromobisethylenediaminecobalt(III)ion in anhydrous NN-dimethylformamide

1966 ◽  
Vol 19 (6) ◽  
pp. 969 ◽  
Author(s):  
IR Lantzke ◽  
DW Watts
Keyword(s):  
Ion Association ◽  
Cobalt Complexes ◽  
Complex Salt ◽  
Ion Pair ◽  
Association Constants ◽  
Halide Ions ◽  
Kcal Mole ◽  
Ion Association Constants ◽  
Dipolar Aprotic Solvents

Using a spectrophotometric technique the ion association constants for three systems of octahedral cobalt complexes and halide ions have been determined at three temperatures in NN-dimethylformamide. The values of K, ΔH�, and ΔS� for each system have been calculated. At 30� they are as follows: cis-[CoCl(DMF) en2]2+ + Cl- ↔ ion pair K=1.51�0.03 x 104 1.mole-1(ΔH0= 0.93 � 0.02 kcal mole-1,ΔS�= 22.l+0.4 e.u) cis-[CoCl(DMF) en2]2++2Cl- ↔ ion triplet K= 1.21�0.05 X 106 1.2 mole-2(ΔH�=-3.8�0.lkcal mole-1, ΔS�=15.41� 0.5 e.u) cis-[CoCl(DMF) en2]2++Br- ↔ ion pair K= 9.20�0.18 X 103 1.1 mole-1(ΔH�=-7.2�0.lkcal mole-1, ΔS�=42� 1.0 e.u) cis-[CoBrCl en2]+ + Br- ↔ ion pair K = 690�l41. mole-1 (ΔH� = 1.27�0.03 kcal mole-1, ΔS�= 8.8�0.2 e.u.) The dependence of the measured K, the association constant, on the wavelength of measurement, small amounts of water in the solvent, and the anion of the complex salt, has also been investigated.

Activity coefficient assumptions in the determination of the association constant of thallium(I) chloride. III. Effects of other association reactions

1967 ◽  
Vol 20 (12) ◽  
pp. 2633 ◽  
Author(s):  
KH Khoo ◽  
MH Panckhurst
Keyword(s):  
Activity Coefficient ◽  
Sodium Acetate ◽  
Association Constant ◽  
Specific Interaction ◽  
Mixed Solvents ◽  
Sodium Perchlorate ◽  
Barium Chloride ◽  
Interaction Coefficients ◽  
Free Ions

Measurements are reported of the solubility of thallium(I) chloride in aqueous solutions of sodium acetate and thallium(I) perchlorate and in solutions of sodium chloride, barium chloride, and sodium perchlorate in 16.7, 30, and 60 wt. % methanol-water mixtures. The measurements in water are used to test the merits of two types of ionic activity coefficient expression. It is shown that it is necessary to take account of specific interactions between free ions and that this also allows for small amounts of other association reactions in the same solution. The possibility of allowing for subsidiary association without using specific interaction coefficients is discussed, and it is concluded that this cannot be done in a completely satisfactory way. Measurements in mixed solvents are used to determine association parameters for the complex TlCl.

Activity coefficient assumptions in the determination of the association constant of thallium(I) chloride. IV. Spectrophotometric measurements on thallium(I) chloride solutions

1969 ◽  
Vol 22 (2) ◽  
pp. 317 ◽  
Author(s):  
JB Macaskill ◽  
MH Panckhurst
Keyword(s):  
Activity Coefficient ◽  
Aqueous Solutions ◽  
Association Constant ◽  
Association Constants ◽  
Chloride Solutions ◽  
Optical Absorbance ◽  
Different Types

Precise measurements are reported of the optical absorbance of aqueous solutions of thallium(I) chloride in mixture with other electrolytes at 25�. Two types of activity coefficient expressions are used to analyse the measurements in terms of association of thallium(I) chloride. The method of analysis is similar to that used for solubility measurements1-3 and the different types of measurements lead to different values for the association constants.

Activity coefficient assumptions in the determination of the association constant of thallous chloride

1964 ◽  
Vol 17 (5) ◽  
pp. 522 ◽  
Author(s):  
JB Macaskill ◽  
MH Panckhurst
Keyword(s):  
Sodium Chloride ◽  
Ionic Strength ◽  
Activity Coefficient ◽  
Association Constant ◽  
Specific Interaction ◽  
Sodium Perchlorate ◽  
Ionic Activity ◽  
Different Types

The solubility of thallous chloride has been measured in sodium chloride and sodium perchlorate solutions at an ionic strength less than 0 1M. The association constant of thallous chloride has been determined from these measurements using two different types of ionic activity coefficient expression, one of them incorporating Br�nsted's principle of specific interaction. The method for determining the association constant gives all the parameters in the treatment but the two activity coefficient expressions give different sets of parameters. These are discussed.

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