Thermochemical constant

The physical and thermochemical constants of anhydrous oxahc acid and oxahc acid dihydrate are summari2ed in Table 1. 

Hirschfelder-Sherman Calculation of Thermochemical Constants for Propellants. See A.M. 

Appendix 1 presents numerous reference tables containing most important data on the solubility of inorganic compounds in water, the density, dissociation constants, solubility products, ionization potentials of various atoms, etc., as well as thermochemical constants because many laws of inorganic chemistry cannot be explained without these quantities. 

From the thermochemical data quoted, Gray, Pratt and Larkin [14] have calculated both the heat of formation of ethyl nitrate at 25°C and other thermochemical constants including the latent heat of evaporation. These data are collected in Table 24. 

TABLE 11. Some thermochemical constants for the AtC6H4CF3 isomers and for allyl astatide... 

Thermal Decomposition.— This is only available when the dissociation of the radical does not occur much more readily than that of the parent molecule. It has not so far been possible to heat a gas rapidly enough to produce radicals instantaneously at high concentrations for kinetic studies and the method is limited to systems in thermodynamic equilibrium which have, however, one great advantage if the thermochemical constants are known the radical concentration and hence its absorption coefficients can be determined. ... 

Each of the groups CHg, C = H., C = H, CHgOH, CHO, CO, etc., has a definite heat of combustion, its so-called thermochemical constant. We can calculate the heat of combustion of any compound by adding the thermo-chemical constants of all the groups in the molecule. Conversely, we can make important deductions from the heat of combustion as to the constitution of a compound. We can decide, for example, the existence of double or triple bonds in this way. 

The quantity n T) can be determined from thermochemical data which determine the value of the T,-, / = 0, 1, 2,. . . , from the third law which determines Sq and therefore I, and finally from the arbitrary constant ho. Nemst called / the thermochemical constant. ... 

HEATS OF ATOMIZATION AND SOME THERMOCHEMICAL CONSTANTS OF A B COMPOUNDS ... 

The relative scarcity of information on the thermochemical constants of compounds... 

Thus, some of the thermochemical constants (the heat of atomization, the entropy, and the specific heat) can be found by summing the correspondii constants of elemental group TV semiconductors. These elements must be chosen in such a way that the sums of their atomic weights... 

Glushko VP (ed) (1981) Thermochemical constants of substances. USSR Academy of Sciences, Moscow (in Russian)... 

As explained in [9], ion work functions are uniquely defined thermochemical constants that can be measured using electrochemical cells with air gaps. Both terms in Equation 13.23 are therefore known from experiment. 

IVTANTHERMO consists of several databases and a set of algorithms and programs. The databases contain auxiliary data, for example, fundamental physical constants, atomic masses of elements etc. -, constants necessary for the calculations of thermodynamic functions primary experimental data on equilibrium constants of chemical reactions and on saturated vapor pressure of substances thermochemical constants tabulated values of thermodynamic properties for wide temperature intervals. 

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