Physical chemistry multicomponent system

The material in this section is divided into three parts. The first subsection deals with the general characteristics of chemical substances. The second subsection is concerned with the chemistry of petroleum it contains a brief review of the nature, composition, and chemical constituents of crude oil and natural gases. The final subsection touches upon selected topics in physical chemistry, including ideal gas behavior, the phase rule and its applications, physical properties of pure substances, ideal solution behavior in binary and multicomponent systems, standard heats of reaction, and combustion of fuels. Examples are provided to illustrate fundamental ideas and principles. Nevertheless, the reader is urged to refer to the recommended bibliography [47-52] or other standard textbooks to obtain a clearer understanding of the subject material. Topics not covered here owing to limitations of space may be readily found in appropriate technical literature. 

Semenovich GM, Lipatov YuS (1986) In Physical chemistry of multicomponent polymer systems. Naukova Dumka, Kiev, p 186... 

A simple classification scheme of solids is given in Fig. 7.1. In order to differentiate between the types of solids, we have to consider the Gibbs phase rule, which is discussed in any physical chemistry textbook. The basic question is whether the solid substance consists of only one chemical entity (component) or more than one. Usually the component is one molecular unit, with only covalent bonded atoms. However, a component can also consist of more constituents if their concentration cannot be varied independently. An example of this is a salt. The hydrochloride salt of a base must be regarded as a one-component system as long as the acid and the base are present in a stoichiometric ratio. A deficiency of hydrochloric acid results in a mixture of the salt and the free base, which behave as two completely different substances (i.e. two different systems). Polymorphic forms, the glassy state, or the melt of the base (or the salt) are considered as different phases within such a system (a phase is defined as the portion of a system that itself is homogeneous in composition but physically distinguishable from other phases). When the base (or salt) is dissolved in a solvent, a new system is obtained this is also tme when a solvent is part of the crystal lattice, as in the case of a solvate. Thus, each solvate represents a different multicomponent system of a compound, whereas, polymorphic forms are different phases. The variables in the solvate are the kind of solvate (hydrate. 

R.A. Veselovsky, Digest of Physical Chemistry of Multicomponent Polymer Systems, Vol. 1, Naukova Dumka, Kiev, p. 375 (1986). 

Modern materials science is mainly based on three sections of physical chemistry, namely, the thermodynamics of multicomponent multiphase systems, the kinetics of phase transitions, and morphology. I he location of the configurative point on the state diagram, the trajectory ajid velocity of its transfer determine the type of phase separation and the mechanism of kinetics, which, in turn, determines the morphology of the system, and, finally, the performance of materials and articles. 

The vehicle format we have used to produce aquasomes is the complex particulate multicomponent system. In general, complex particulate delivery systems are assemblies of simple polymers, complex lipid mixtures or ceramic materials that tend to measure individually between 30 and 500 nm in diameter. Being solid or glassy particles dispersed in an aqueous environment, they exhibit the physical properties of colloids their mechanism of action is controlled by their surface chemistry. They may deliver agents through a combination of specific targeting, molecular shielding, and slow release processes. 

Tersoff, J. (1989), Modeling solid-state chemistry Interatomic potentials for multicomponent systems. Physical Review B 39, 5566-5568. 

G. Semenovich and Y. Lipatov in Physical Chemistry of Multicomponent Polymer Systems, Ed. Y. Lipatov, Naukova Durtika, Kiev, vol. 1, p.l86 (1986). 

V. F. Shumsky in Physical Chemistry of Multicomponent Polymer Systems,... 

Pentrakoon D (1995) PhD thesis. University of Massachusetts Lipatov YS, Rosovitsky VF (1976) Rep Acad Sci Ukrainian SSR B8 713 Rosovitsky VF, Lipatov YS (1986) In Physical chemistry of multicomponent polymeric systems, vol 2. Naukova Dumka, Kiev, p 229... 

Lebedev E.V. // Fizikokhimija Mnogokomponentnykh Polimemykh System (Physical Chemistry of Multicomponent Polymer Systems. - Kiev Nauk. Dumka, 1986, V.2, P. 121 (in Russian). 

Data of Azeotropes. The choice of azeotropic entrainer for a desired separation is much more restricted than that of solvents for extractive distillation, although many azeotropic data are known. The most extensive compilation is that of Ogorodnikov, Lesteva, and Kogan (Handbook of Azeotropic Mixtures (in Russian), 1971). It contains data of 21,069 systems, of which 1274 are ternary, 60 multicomponent, and the rest binary. Another compilation Handbook of Chemistry and Physics, 60th ed., CRC Press, Boca Raton, FL, 1979) has data of 685 binary and 119 ternary azeotropes. Shorter lists with grouping according to the major substances also are available in Lange s Handbook of Chemistry... 

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