Index of content:
Volume 16, Issue 3, July 1987

Standard Chemical Thermodynamic Properties of Alkanol Isomer Groups
View Description Hide DescriptionThe chemical thermodynamic properties of alkanol(ROH) isomer groups from CH_{4}O to C_{4}H_{1} _{0}O in the ideal gas phase have been calculated from 298.15 to 1000 K from tables of Stull, Westrum, and Sinke. In the absence of literature data on all isomers of higher isomer groups, the properties of isomers of C_{5}H_{1} _{2}O to C_{8}H_{1} _{8}O have been estimated using Benson group values. Equilibrium mole fractions within isomer groups have been calculated for the ideal gas state from 298.15 to 1000 K. For isomer group properties increments per carbon atom have been calculated to show the extent to which thermodynamic properties of higher isomer groups may be obtained by linear extrapolation. Values of C ^{○} _{ P }, S ^{○}, Δ_{f} H ^{○}, and Δ_{f} G ^{○} are given for all species of alkanols from CH_{4}O to C_{8}H_{1} _{8}O in SI units for a standard state pressure of 1 bar.

High‐Temperature Vaporization Behavior of Oxides II. Oxides of Be, Mg, Ca, Sr, Ba, B, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Zn, Cd, and Hg
View Description Hide DescriptionIn order to assess the high‐temperature vaporization behavior and equilibrium gas phase compositions over the condensed oxides of Be, Mg, Ca, Sr, Ba, B, Al, Ga, In, Tl, Si, Ge, Sn, Pb,Zn, Cd, and Hg, the relevant thermodynamic and molecular constant data have been compiled and critically evaluated. Selected values of the Gibbs energy functions of condensed and vapor phases are given in the form of equations valid over wide temperature ranges, along with the standard entropies and enthalpies of formation. These data were used to generate plots of equilibrium partial pressures of vapor species as functions of temperature for representative environmental conditions ranging from reducing to oxidizing. The calculated partial pressures and compositions agree, for the most part, with experimental results obtained under comparable conditions. Maximum vaporization rates have been calculated using the Hertz–Knudsen equation. Literature references are given.

Equilibrium and Transport Properties of Eleven Polyatomic Gases At Low Density
View Description Hide DescriptionThis study presents a computer programmable, thermodynamically consistent representation of the second virial coefficient B, viscosity η, self‐diffusion coefficient D, and isotopic thermal diffusion factor α_{0} of the eleven gases: N_{2}, O_{2}, NO, CO, N_{2}O, CO_{2}, CH_{4}, CF_{4}, SF_{6}, C_{2}H_{4}, and C_{2}H_{6}, all at low density. Limited thermodynamic consistency is achieved by the use of four scaling parameters (σ, ε, V ^{*} _{0}, ρ*) in addition to the molecular weight. In terms of these parameters, the collision integrals for the transport properties obey a single law of corresponding states. Furthermore, Ω^{(2,2)*} (T) is the same as that for the universal correlation of the monatomic gases [J. Chem. Phys. Ref. Data 1 3, 229 (1984)] whereas Ω^{(1,1)*} (T) is only slightly modified. The same parameters nearly correlate the spherical part B _{0}(T)=B(T)−B _{ns}(T) of the second virial coefficient corrected for the most important nonspherical influences; its dimensionless form B ^{*} _{0}(T) differs from that for the monatomic gases and also, somewhat, for each of the eleven gases, except that one form suffices for N_{2}, O_{2}, NO, CO. The correlations embrace the reduced temperature range 1<T*<10 with the parameters σ and ε, and the range T*>10 with the parameters V ^{*} _{0} and ρ* derived from high‐energy beam experiments. The accuracy achieved is carefully specified, and

The Thermochemistry of Inorganic Solids IV. Enthalpies of Formation of Compounds of the Formula MX_{ a }Y_{ b }
View Description Hide DescriptionIt is found that the standard enthalpies of formation Δ_{f} H ^{○} _{298} of double salts of the type MX_{ a }Y_{ b } are related by a simple additivity relation to Δ_{f} H ^{○} _{298} of their binary salts MX_{ c } and MY_{ d }. For divalent metals M this relation takes the form, Δ_{f} H ^{○} _{298}(MXY) = 1/2 Δ_{f} H ^{○} _{298}(MX_{2})+ 1/2 Δ_{f} H ^{○} _{298}(MY_{2})+C, with C=−13.4 or −17.6 kJ/mol giving equally good fits to the data. From a lesser number of data for trivalent and tetravalent metals M, one finds again a simple additivity relation of the form Δ_{f} H ^{○} _{298}(MX_{ a }Y_{ b }) =(a x/z)Δ_{f} H ^{○} _{298}(MX_{ z/x }) +(b y/z)Δ_{f} H ^{○} _{298}(MY_{ z/ y })+C, where x, y, and z are the formal valences of X, Y, and M, respectively, so that z=a x+b y, and C=0. For 16 divalent metal compounds average deviations are 5.5 kJ/mol with a maximum deviation of 10.7 kJ/mol. For eight trivalent metal compounds the average deviations are 13.9 kJ/mol with a maximum of 50.6 kJ/mol. For five tetravalent compounds, the average deviations are 3.5 kJ/mol with a maximum of 6.3 kJ/mol.

Chemical Kinetic Data Base for Combustion Chemistry. Part 2. Methanol
View Description Hide DescriptionThis publication contains evaluated and estimated data on the kinetics of reactions involving methanol and hydroxymethyl radicals and various small inorganic and organic species which are of importance for the proper understanding of methanol combustion and pyrolysis. It is meant to be used in conjunction with the kinetic data given in an earlier publication pertaining to methanepyrolysis and combustion, but which also contains a large volume of data that are applicable to the methanol system. The temperature range covered is 300–2500 K and the density range 1×10^{1} ^{6} to 1×10^{2} ^{1} molecules cm^{−} ^{3}.

Phase Diagrams and Thermodynamic Properties of the 70 Binary Alkali Halide Systems Having Common Ions
View Description Hide DescriptionA very extensive literature survey of all available phase diagram and thermodynamic data has been carried out for all 40 possible common‐anion binary systems (AX‐BX) and all 30 possible common‐cation binary systems (AX‐AY) involving the alkali halides (A,B =Li,Na,K,Rb,Cs; X,Y=F,Cl,Br,I). A critical analysis and evaluation of these data have been performed with a view to obtaining a ‘‘best’’ evaluated phase diagram and a set of ‘‘best’’ evaluated thermodynamic parameters for each system. To this end, a computer‐assisted coupled analysis of the phase diagram data and the thermodynamic data for each system has been employed. Mathematical expressions for the thermodynamic properties of all known phases have been obtained which are consistent with the measured thermodynamic properties and phase diagrams as well as with established thermodynamic principles and theories of solution behavior. The parameters of these expressions are reported here and have been used to generate the computer‐calculated diagrams in the compilation.