Density, molar volume

According to the definition, a density, p, of system is the volume-additive function of composition  

From [9.33], it follows that molar volume of ideal system is a molar-additive function of composition  

Molar mass of mixture, according to the definition, is a molar-additive function too  

For two-component mixture of solvents, these relations are as follows  

Non-ideality of the system leads to relative deviations of density and molar volume, as well as of other volumetric properties, having magnitude of about 1%. Flere, contraction and expansion of solutions are approximately equiprobable. In systems in conditions close to separation, considerable contraction is possible. Flowever, two component systems formed from the most common solvents, used in practical applications, form solutions far from separation at usual temperature range. 

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Obama, M., et al., Densities, Molar Volumes, and Cubic Expansion Coefficients of 78 Aliphatic Ethers. J. Chem. Eng. Data, 1985 30, 1-5. 

Density is defined as the mass of a substance per unit volume. Density is given in kg/m in SI units, but lb /ft and g/cm are common AES and cgs units, respectively. Other commonly used forms of density include molar density (density divided by molecular weight) in kmol/m, relative density (density relative to water at 15°C), and the older term specific gravity (density relative to water at 60°F). Often the inverse of density, specific volume, and the inverse of molar density, molar volume, are correlated and used to convey equivalent information. 

Density Molar volume Density Molar volume Density Molar volume... 

The physico-chemical properties such as phase equilibria, density (molar volume), enthalpy (calorimetry), surface tension, vapor pressure, electrical conductivity, viscosity, etc. are the most important parameters of electrolytes needed for technological use. For each property, the theoretical background, experimental techniques, as well as examples of the latest knowledge and the processing of most important salt systems will be given. Most of the examples are among the published works of the author. 

Crystallographic Properties [1.1,1.6]. Besides amorphous tungsten, three modifications (a-, P-, and y-tungsten) are known. Table 1.8 provides crystallographic parameters and related data, such as density, molar volume, and specific volume. 

An intensive property is a characteristic of a system that does not depend on the size of the system. That is, doubling the size of the system leave the value of an intensive property unchanged. Examples of intensive properties are pressure, temperature, density, molar volume, etc. By definition, an intensive property can only be a function of other intensive properties. It cannot be a function of properties that are extensive because it would then depend on the size of the system. 

W. Davis, Jr. October 1962. Thermodynamics of extraction of nitric acid by tri- -butyl phosphate-hydrocarbon-diluent solutions II. densities, molar volumes, and water solubilities of TBP-Amsco 125-82-nitric acid-water solutions. Nuc. Sc. Eng. 14 (2) 169-173. 

Many physical and chemical properties are related to the density of the fluid. Properties such as the isothermal compressibility factor, /Cj, and the coeflicient of thermal expansion, a, are simply derivatives of density (molar volume, V) with temperature or pressure [Eq. (2)]. 

Concentration dependencies of permittivity, viscosity, density (molar volume) and conductivity described here permit to select with certainty the composition of mixed solvent, characterized by any value of mentioned properties. 

For convenience, thermodynamic systems are usually assumed closed, isolated from the surroundings. The laws that govern such systems are written in terms of two types of variables intensive (or intrinsic) that do not depend on the mass and extensive that do. By definition, extensive variables are additive, that is, their value for the whole system is the sum of their values for the individual parts. For example, volume, entropy, and total energy of a system are extensive variables, but the specific volume (or its reciprocity - the density), molar volume, or molar free energy of mixing are intensive. It is advisable to use, whenever possible, intensive variables. 

Volume flux is yet another way to quantify the flux of a species, using the volume rather than mass or moles of the species to describe the rate of transport. Volume flux is related to mass, molar, or number flux by the species density, molar volume, or atomic volume ... 

Boiling and melting points, v >or pressure, fiigacity and activity coefficients, solubility (Henry s constants, Ostwald or Bunsen coefficients), BIPs Density, molar volume, compressibility, critical properties, acentric factor... 

Densities, Molar Volumes, and Refractive Indices for Some Thorium Nitrato Complexes [2]... 

Density Molar volume Melting point Boiling point Specific heat c at 298 K... 

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