Potassium chloride thermodynamic data

Thermodynamic data show that the stabilities of the caesium chloride-metal chloride complexes are greater than the conesponding sodium and potassium compounds, and tire fluorides form complexes more readily tlrair the chlorides, in the solid state. It would seem that tire stabilities of these compounds would transfer into tire liquid state. In fact, it has been possible to account for the heats of formation of molten salt mixtures by the assumption that molten complex salts contain complex as well as simple anions, so tlrat tire heat of formation of the liquid mixtures is tire mole fraction weighted product of the pure components and the complex. For example, in the CsCl-ZrCU system the heat of formation is given on each side of tire complex compound composition, the mole fraction of the compound... 

Calculate a value for the lattice energy of potassium chloride using Equation (1.15). Compare this with the value you calculate from the thermodynamic data in Table 1.20. 

With the use of thermodynamic relations and numerical procedure, the activity coefficients of the solutes in a ternary system are expressed as a function of binary data and the water activity of the ternary system. The isopiestic method was used to obtain water activity data. The systems KCl-H20-PEG-200 and KBr-H20-PEG-200 were measured. The activity coefficient of potassium chloride is higher in the mixed solvent than in pure water. The activity coefficient of potassium bromide is smaller and changes very little with the increasing nonelectrolyte concentration. PEG-200 is salted out from the system with KCl, but it is salted in in the system with KBr within a certain concentration range. 

Pabalan, R., and Pitzer, K. S. (1988) Apparent Molar Heat Capacity and Other Thermodynamic Properties of Aqueous Potassium Chloride Solutions to High Temperatures and Pressures, J. Chem. Eng. Data 33, 354-362. 

The coal ash deposits on boiler tubes have frequently a separate zone structure with a sulphate rich layer up to 2 mm thick under the matrix of sintered ash (3 ). The outer layer is porous and it constitutes a pathway for the enrichment of alkali-metals in the deposit layer next to tube suface. The diffusable species may be sulphate, chloride, oxide or hydroxide, but the thermodynamic data W and the results of deposition measurements in coal fired boilers (Figure 3) suggest that sodium and potassium sulphates are the principal vapour species which diffuse through a porous matrix of silicate ash deposit. 

Kuznetsov, S.A., and Stangrit P.T. (1990). Thermodynamics of the formation of chorimium di - and trichloride from the elements in a molten equimolecular mixture of sodium and potassium chlorides from linear-voltammetry data, Rasplavy 44-48. 

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