Heat capacity isomorphic

Specific Heats of Solid Mixtures.—The specific heat of a homogeneous solid mixture of solid components is not usually additively composed of the specific heats of the latter. W. Spring (1886) found that the total heat capacity of alloys of lead and tin was always greater than the sum of those of the components, but above the melting-point the two were equal. A. Bogojawlensky and N. Winogradoff (1908) find, however, that the heat capacities of the isomorphous mixtures ... 

With the exception of liquid alloys and fused isomorphous mixtures the heat capacity of a mixture of liquids is usually larger than the sum of those of the components, e.g. with mixtures of alcohol with water, chloroform, carbon disulphide, and benzene. The 20 per cent solution of alcohol in water has a specific heat (1 046) greater than that of any other liquid below 100°.8 The heat capacities of mixtures of benzene and chloroform are the sum of those of the components. ... 

Other methods of determining atomic weights X-ray method heat capacity of gases heat capacity of solids isomorphism chendcal analogy. 

The heat capacities of the non-magnetic oxychalcogenides ThOS(cr) and ThOSe(cr) and of the isomorphous antiferromagnetic UOS(cr) and UOSe(cr) were measured from ca. 5 to ca. 300 K. The samples were prepared by mixing stoichiometric amounts of the dioxides and disulphides and annealed in vacuo in silica tubes at 1273 K for three days. X-ray diffraction analysis of the thorium compounds showed the expected PbFCl structure. For ThOS, a weak extra line due to Th02 was detected, and for ThOSe, several non-identified very weak extra lines were foimd. For the adiabatic heat capacity... 

Povodyreveta/. (1997) have developedasix-term Landau expansion crossover scaling model to describe the thermodynamic properties of near-critical binary mixtures, based on the same model for pure fluids and the isomorphism principle of the critical phenomena. The model describes densities and concentrations at vapor-liquid equflibrium and isochoric heat capacities in the one-phase region. The description shows crossover from asymptotic Ising-hke critical behavior to classical (mean-field) behavior. This model was applied to aqueous solutions of sodium chloride. 

In the restricted linear model the expression for the isomorphic heat capacity (d(p2ldh2), becomes independent of... 

In eq 10.65b Af and ficr now refer to the critical behaviour of the isomorphic specific heat capacity which for liquid mixtures is the isobaric specific heat capacity. 

In fact, the contribution of electronic conductivity can be ignored because it is quite small. The major contribution to Cp arises from the lattice (vibrational) component Cy, which varies linearly as a function of molar volume V in a series of isomorphous compounds. For the com-poimds imder study, Cy can therefore be estimated using volume-weighted interpolation (Westrum et al., 1989) and data on isomorphous diamagnetic substances as reference values. For instance, the Cy heat capacities measured for trivalent lanthanum, gadolinium, and lutetium compoimds were used as reference values. Subsequently, the Cm and Csch contributions were determined by subtracting the sum of the Cy and Cd contributions from the experimental Cp values. 

Crystal structure. The crystalline complexes (tt-CsHs) —, —V, —Cr, —Fe, —Co, —Ni, are isomorphous and have a monoclinic form [57]. On rapid cooling of crystalline ferrocene the crystals disintegrate fairly violently to a powder. Studies on the heat capacity of ferrocene have shown that there is a A point transition at 163 9°K the A range is about 125-200 K [58]. 

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