Zinc selenate solution

Banks [34BAN] made careful measurements of the conductivity of zinc selenate solutions at 298.15 K. The concentration range used was approximately 2 x 10 to 1 X 10 M. On the assumption that only ZnSe04(aq) was formed the data were evaluated by an iterative procedure in which the inter-ionic attraction was corrected for using the Debye-Huckel (activity coefficient) and Onsager (ionic mobility) equations. The result for ... 

Selenium powder is insoluble in water the dioxide, selenous acid, and the alkali metal selenites are water soluble. Highly poisonous hydrogen selenide (offensive smell) is generated when an acid solution of a selenium compound is reduced by metals such as tin and zinc. Selenic acid reacts vigorously with water.1... 

Aruga [78ARU] made calorimetric titrations of 0.17 M zinc nitrate solution with 0.17 M tetraethylammonium selenate, see Appendix A. The concentration of ZnSe04(aq) formed was calculated with the equilibrium constant determined in [34BAN] corrected to / = 0.5 M by Davies equation. After experimentally determined corrections for heats of dilution had been applied, the enthalpy change of Reaction (V.80) was calculated to be A //, ((V.80), / = 0.5 M, 298.15 K) = (0.20 0.05) kJ-moP. The recalculation of the equilibrium constant to / = 0.5 M is uncertain. The uncertainty assigned by the author to A,//° has therefore been increased to include the uncertainty in the value of the equilibrium constant. 

Christov calculated the parameters in the Pitzer ion interaction model from isopiestie measurements at 298.15 K by Ojkova and Staneva [890JK/STA]. This reference contains (interpolated) osmotic coefficients of zinc, magnesium, cobalt, and nickel selenate solutions from 0.1 mol-kg to saturated solution. Sodium chloride standards were used and the agreement between duplicate determinations was 0.2% or better. 

Aruga [78ARU] made calorimetric titrations of 0.17 M cadmium nitrate solution with 0.17 M tetraethylammonium selenate, see Appendix A. The evaluation of the experiment was made as described for zinc in Section V.9.1.3. The selected result is ... 

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