Chlorides thermodynamic properties

Anhydrous Hydrogen Chloride. Anhydrous hydrogen chloride is a colorless gas that condenses to a colorless liquid and freezes to a white crystalline solid. The physical and thermodynamic properties of HCl are summarized in Table 2 for selected temperatures and pressures. Figure 1 shows the temperature dependence of some of these properties. 

Table 2. Physical and Thermodynamic Properties of Anhydrous Hydrogen Chloride...

Physical Properties. Thionyl chloride [7719-09-7], SOCI2, is a colorless fuming Hquid with a choking odor. Selected physical and thermodynamic properties are Hsted in Table 6. Thionyl chloride is miscible with many organic solvents including chlorinated hydrocarbons and aromatic hydrocarbons. It reacts quickly with water to form HCl and SO2. Thionyl chloride is stable at room temperature however, slight decomposition occurs just... 

Physical Properties. Sulfuryl chloride [7791-25-5] SO2CI2, is a colorless to light yellow Hquid with a pungent odor. Physical and thermodynamic properties are Hsted ia Table 7. Sulfuryl chloride dissolves sulfur dioxide, bromine, iodine, and ferric chloride. Various quaternary alkyl ammonium salts dissolve ia sulfuryl chloride to produce highly conductive solutions. Sulfuryl chloride is miscible with acetic acid and ether but not with hexane (193,194). 

The increasing ranges of pressure and temperature of interest to technology for an ever-increasing number of substances would necessitate additional tables in this subsection as well as in the subsec tion Thermodynamic Properties. Space restrictions preclude this. Hence, in the present revision, an attempt was made to update the fluid-compressibihty tables for selected fluids and to omit tables for other fluids. The reader is thus referred to the fourth edition for tables on miscellaneous gases at 0°C, acetylene, ammonia, ethane, ethylene, hydrogen-nitrogen mixtures, and methyl chloride. The reader is also... 

Good electrical conductance is one of the characteristics of many though not all molten salts. This characteristic has often been employed industrially. Various models have been proposed for the mechanism of electrical conductance. Electrolytic conductivity is related to the structure, although structure and thermodynamic properties are not the main subjects of this chapter. Electrolytic conductivities of various metal chlorides at the melting points are given in Table 4 together with some other related properties. "... 

Calcium-sodium-chloride-type brines (which typically occur in deep-well-injection zones) require sophisticated electrolyte models to calculate their thermodynamic properties. Many parameters for characterizing the partial molal properties of the dissolved constituents in such brines have not been determined. (Molality is a measure of the relative number of solute and solvent particles in a solution and is expressed as the number of gram-molecular weights of solute in 1000 g of solvent.) Precise modeling is limited to relatively low salinities (where many parameters are unnecessary) or to chemically simple systems operating near 25°C. 

Anhydrous copper(II) sulfate, 7 773 Anhydrous ethanol, production by azeotropic extraction, 8 809, 817 Anhydrous gaseous hydrogen sulfide, 23 633 Anhydrous hydrazine, 13 562, 585 acid-base reactions of, 13 567-568 explosive limits of, 13 566t formation of, 13 579 vapor pressures of, 13 564 Anhydrous hydrogen chloride, 13 809-813 physical and thermodynamic properties of, 13 809-813 purification of, 13 824-825 reactions of, 13 818-821 uses for, 13 833-834... 

Methylammonium chloride exits in several crystalline forms, as is evident from Figure 11.3. The thermodynamic properties of the (3 and 7 forms have been investigated by Aston and Ziemer [10] down to temperatures near 0 K. Some of their data are listed below. From the information given, calculate the enthalpy of transition from the (3 to the 7 form at 220.4 K. 

The effect of temperature on the thermodynamic properties and the CMC is shown in Figure 18.13, where 4>L, < >CP and (f>V at three temperatures are graphed as a function of the molality m for n-dodecylpyridinium chloride. We can interpolate the results in Figure 18.13a to determine that L at the CMC is near zero for this surfactant at a temperature near, but just above, 298.15 K. When 4>L = 0, the CMC is at its minimum value. We will better understand why as we consider theories for describing the curves shown in Figures 18.11 and 18.13. 

Equations used to calculate L and 4>CP are taken from K. S. Pitzer, Ion interaction approach theory and data correlation , Chapter 3 in Activity Coefficients in Electrolyte Solutions, 2nd Edition, K. S. Pitzer, Editor, CRC Press, Boca Raton, Florida, 1991. Equations for calculating L, L2, Ju and J2 are summarized in K. S. Pitzer, J. C. Peiper, and R. H. Busey, Thermodynamic properties of aqueous sodium chloride solutions , J. Phys. Chem. Ref Data, 13, 1-102 (1984). 

The thermodynamic properties at T = 298.15 K shown in Figure 18.11 come from S. Causi, R. De Lisi, and S. Milioto, Thermodynamic properties of N-octyl-, N-decyl- and N-dodecylpyridinium chlorides in water , J. Solution Chem., 20, 1031-1058 (1991). Results at the other two temperatures are courtesy of K. Ballerat-Busserolles, C. Bizzo, L. Pezzimi, K. Sullivan, and E. M. Woolley, Apparent molar volumes and heat capacities at aqueous n-dodecyclpyridium chloride at molalities from 0.003 molkg-1 to 0.15 molkg-1, at temperatures from 283.15 K. to 393.15 K, and at the pressure 0.35 MPa , J. Chem. Thermodyn., 30, 971-983 (1998). 

The thermodynamic treatment of systems in which at least one component is an electrolyte needs special comment. Such systems present the first case where we must choose between treating the system in terms of components or in terms of species. No decision can be based on thermodynamics alone. If we choose to work in terms of components, any effect of the presence of new species that are different from the components, would appear in the excess chemical potentials. No error would be involved, and the thermodynamic properties of the system expressed in terms of the excess chemical potentials and based on the components would be valid. It is only when we wish to explain the observed behavior of a system, to treat the system on the basis of some theoretical concept or, possibly, to obtain additional information concerning the molecular properties of the system, that we turn to the concept of species. For example, we can study the equilibrium between a dilute aqueous solution of sodium chloride and ice in terms of the components water and sodium chloride. However, we know that the observed effect of the lowering of the freezing point of water is approximately twice that expected for a nondissociable solute. This effect is explained in terms of the ionization. In any given case the choice of the species is dictated largely by our knowledge of the system obtained outside of the field of thermodynamics and, indeed, may be quite arbitrary. 

Bates, R.G. and Bower, V.E., Standard potential of the silver silver-chloride electrode from 0-degrees C to 95-degrees C and the thermodynamic properties of dilute hydrochloric acid solutions, J. Res. Natl. Bur. Stand., 53, 283, 1954. 

A new thermodynamic model for the Cu(I,II)-HC1-H20 system was developed on the basis of the representative data on GuGl(s) solubility in aqueous solutions of HC1 in a concentration interval from 1 to 6 mol kg1 HG1 (Akinfiev, 2009). The model takes into account a number of aqueous Cu(I) species [Cu+, CuOH°, Cu(OH)2, CuC1°, CuClj, HCuCL ], aqueous Cu(II) species [Cu2 CuOH+, CuO°, HCuO , CuOJ- CuCl+, CuCL , GuGlg, CuClJ)] and a mixed Cu(I)/Cu(II) chloride aqueous complex, Cu2Cl . The thermodynamic approach used a modelling approach based on i) the standard thermodynamic properties of the listed above species ii) a model for the activity coefficients iii) use of HCh software (Shvarov, 1999). 

The free energy term, 8AGtI, is obtained with relative ease from Henry s law constants. Thus, complete dissection of the effect of solvent on the various thermodynamic properties is possible in favourable cases. This was in fact achieved by Arnett et al. (1965) for the solvolysis of t-butyl chloride in aqueous ethanol mixtures and revealed that the peculiar rate variation with changing solvent composition was largely caused by changes in the initial state interactions. 

---