Solubility product from conductance

To determine the sohibility of AgCl in water at 18 C and at 25 C from measurements of conductance. 

Kohlrausch determined the molar conductance A of many salts over a wide range of concentrations and their temperature coefficients. By adding the values for KCl and AgNOg and then subtracting the value for KNOj Kohlrausch (Z. physikal. Chem. 1908,44,129) obtained 

For the conductivity (specific conductance) x of saturated solutions of AgCI in water he found 

From the experimental value of x of the saturated solution at each temperature we calculate the theoretical value of at 18 °C for the solution (unsaturated or supersaturated) of the same concentration. We divide this value of x by the appropriate value of A determined, if necessary, by successive approximations to obtain the concentration of the saturated solution. 

To obtain values at 18 C and at 25 C the best interpolation is a linear one of log s with respect to T. Over such a short temperature inteiv al it is however adequate to use a linear interpolation of log s with respect to t. We thus obtain 

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The environment plays several roles in corrosion. It acts to complete the electrical circuit, ie, suppHes the ionic conduction path provide reactants for the cathodic process remove soluble reaction products from the metal surface and/or destabili2e or break down protective reaction products such as oxide films that are formed on the metal. Some important environmental factors include the oxygen concentration the pH of the electrolyte the temperature and the concentration of anions. 

Table VI liststhe calculated Px,y/Fy vaiues for the three soluble coal products from E10 and E19. The values range from 0.58 to 1.63. The a-alkyl regions in E10 and E19 have Px,y >fy which indicate that in liquefaction experiments conducted with a donor solvent, preferential incorporation occurs in the a-alkyl position.

In the 2nd period ranging from the 1930s to the 1950s, basic research on flotation was conducted widely in order to understand the principles of the flotation process. Taggart and co-workers (1930, 1945) proposed a chemical reaction hypothesis, based on which the flotation of sulphide minerals was explained by the solubility product of the metal-collector salts involved. It was plausible at that time that the floatability of copper, lead, and zinc sulphide minerals using xanthate as a collector decreased in the order of increase of the solubility product of their metal xanthate (Karkovsky, 1957). Sutherland and Wark (1955) paid attention to the fact that this model was not always consistent with the established values of the solubility products of the species involved. They believed that the interaction of thio-collectors with sulphides should be considered as adsorption and proposed a mechanism of competitive adsorption between xanthate and hydroxide ions, which explained the Barsky empirical relationship between the upper pH limit of flotation and collector concentration. Gaudin (1957) concurred with Wark s explanation of this phenomenon. Du Rietz... 

Analytical data on the soluble products isolated from chloroform are in excellent agreement with the composition 1 Ni+2 1 monoalkylated ligand 1 I or Br. The magnetic moment of this methylated complex was found to be 1.89 Bohr magnetons per nickel (II). The molar conductivities of the methylated and benzylated complexes in methanol at 25° C. are 75.4 and 68.4 ohm-1, respectively. These values approximate those expected for uni-univalent electrolytes in this solvent. The formulation of these alkylated compounds as dimeric electrolytes (structure VII) does not appear to be totally consistent with their physical properties. One or both halide ions may be bound to the metal ion. These results lead to the easily understood generalization that terminal sulfur atoms alkylate more readily than bridged mercaptide groups. 

Anodic oxidation of pyrrole and N-substituted pyrroles results in the formation of polypyrroles in an oxidized state, which can be useful for the preparation of conducting organic polymers.185-188 Oxidation of 2,5-di-substituted pyrroles produces soluble products and no layer of polymers.187 One of the proposed applications of such a layer of conducting polymer is the protection of semiconductor electrodes from photocorrosion.189-191... 

It is a function expressing the effect of charge of the ions in a solution. It was introduced by -> Lewis and Randall [iii]. The factor 0.5 was applied for the sake of simplicity since for 1 1 electrolytes I = c (electrolyte). It is an important quantity in all electrostatic theories and calculations (e.g., - Debye-Huckel theory, - Debye-Htickel limiting law, - Debye-Huckel-Onsager theory) used for the estimation of -> activity coefficients, -> dissociation constants, -> solubility products, -> conductivity of -> electrolytes etc., when independently from the nature of ions only their charge is considered which depends on the total amount (concentration) of the ions and their charge number (zj). 

Chantooni and Kolthoff " derived equations which permit the calculation of hydration constants of cations and anions from the solubility products of slightly soluble salts in solutions of acetonitrile with various concentrations of water. The ionic solubility of a salt was determined by measuring the conductance. The water concentration of the acetonitrile solution was always less than 1 M. The total ionic solubility product was expanded in powers of the water concentration. The coefficients are related to the individual ionic hydration constants and were evaluated by... 

In the aqueous phase, Umland and Wallmeier [80UML/WAL] attempted to determine the solubility product of Sb2Se3(cr) by the polarographic method outlined in Appendix A. Their result, log (Sb2Sc3, cr, 298.15 K) = - (113 2), is not accepted since the measurements were conducted in presence of 0.5 M tartaric acid and, therefore, the conditions for the evaluation of the constant from the measurements are not fulfilled. 

As described in Appendix A, Ripan and Vericeanu [68RIP/VER] studied the solubility of zinc selenite by conductivity measurements. A calculation based on the equilibrium constants in [76BAE/MES] and the total concentrations provided in the paper, mean 1.40 x 10 M, leads to the conclusion that about 30% of dissolved Zn(ll) would be present in hydrolysed forms, if the solvent were conductivity water. No reliable solubility product can therefore be derived from the conductivity data. The value logio = -(7.71+0.05) was estimated by Masson, Lutz and Engelen [86MAS/LUT] from the data, but the composition of the solid phase is apparently not known. 

Ripan and Vericeanu [68R1P/VER] studied the solubility of CuSe03-2H20(s) by conductivity measurements as described in Appendix A. An equilibrium analysis performed as outlined there on the total concentrations provided in the paper, about 1.8 X 10 M, leads to the conclusion that almost 80% of the copper(II) would be present as hydroxo complexes at equilibrium. Hence, a conductivity measurement is unsuitable for the determination of the solubility of copper selenite and no reliable value of the solubility product can be calculated from the data in [68R1PA ER]. Masson et al. [86MAS/LUT] calculated log (, = - (7.49 0.10) from the data neglecting hydrolysis of Cu. ... 

Solubility Product. If calcium sulfate powder (gypsum) is mixed well with water and the suspension is left to stand, a white solid sinks down to the bottom (see E6.5). The question arising from the amount of solid substance is whether a part of the calcium sulfate dissolves or if the substance is insoluble. Testing the electrical conductivity (see E6.5), however, shows a much higher value than with distilled water calcium sulfate dissolves in very minute amounts a dynamic equilibrium is formed between the solid residue and the saturated solution ... 

After correcting for the conductivity of the solvent, the conductivity of a saturated solution of silver bromide in water is 6.99 x 10 S cm at 18°C. If the molar ionic conductivities of Ag" (aq) and Br (aq) are 53.5 and 68.0 S cm mol respectively, find the solubility of silver bromide in water. From this calculate the solubility product for silver bromide. 

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