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Home >> Chemistry Dictionary >> Clausius Mosotti Law Coagulation
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Clarifier. Large tanks with continuous feed and outflow in which the suspended matter is allowed to settle and is removed. Clarifiers are generally similar to thickeners except that they handle smaller quantities of solids.
Classification. The process of separating a mixture of particles into two or more fractions according to size, sape, density, magnetic properties, etc.
Clathrate compounds. Molecular compounds formed by the inclusion of molecules of one type in holes in the latticed of another. Used in the separation of, e.g. gases.
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Clatherates. A group of chemical substances in which small molecules or atoms of one species are trapped inside a cage like structure former from the crystals of another substance e.g. urea forms a series of such compounds with the alkanoic acids and noble gases can similarly be trapped inside quinol crystals. There are no bonds between the crystals and the trapped molecules.
Claude process. A process for liquefying air on a commercial basis.
Clausius mosotti law. The molecular polarization (P) of a substance of molecular weight M density d and dielectric constant D is :
P = 
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Clays. Natural aluminosilicates which occur as a plastic or can be covered to a paste by grinding or mixing with water. When dried and ground clay particles can be suspended in water almost indefinitely; suspension is aided if a small amount of Na2CO3 is added. Gels may be formed in concentrated suspension.
Clays have layers of linked (Al, Si) O4 tetrahedra combined with layers of Mg(OH)2 or Al(OH)3. clays are very important soil constituents and are used in pottery, ceramics, as rubber, paint, plastic and paper fillers, as adsorbents and in drilling muds.
Clay treatment. Removal of by-products and acid-sludge from oils by adsorption on clay.
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Cleavage planes. Directions in a crystal in which there is ready cleavage. Cleavage planes often correspond to layers of atoms of molecules in the lattice.
Clemmensen reduction. Aldehydes and ketones may generally be reduced to the corresponding hydrocarbons by heating with amalgamated zinc and hydrochloric acid.
Clinker. A hard mass of material which is not combindible obtained infornaces and boiler fires. It is composed of calcium silicate formed by fusion of earthy material in fuels and ores.
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Close-packed structures. The packing of spheres so as to occupy the minimum amount of space. In a single plane, each sphere is surrounded by six close neighbours in a hexagonal arrangement. The spheres in the second plane fit into depressions in the first layer, and so on. Each sphere has 12 other touching spheres. There are two types of close packing. In hexagonal close packing the spheres in the third layer and directly over those in the first, etc. and the arrangement of planes in ABAB…… In cubic close packing the spheres in the third layer occupy a different set of depressions than those in the first. The arrangement is ABCABC.
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Clupeine. Protamine class protein found in the sperm and testicles of the hearing. On hydrolysis it gives about 90% of argenine.
Clusius column. A device for separating isotopes by thermal diffusion.
Cluster compounds. Compounds containing group of metal atoms joined by metal-metal bonds, e.g. [Rh6(CO)16], [Mo6Cl8]+
Cm. Curium.
Co. Cobalt.
Coacervation. The process of separation of lyophilic particles from a colloid. Some colloids are coagulated by the addition of chemicals, by vibration, electric current or heat.
Coagel. A gelatinous precipitate, e.g. rigid silica gel.
Coagulation. The formation of a large, non-dispersed particles from a colloid. Some colloids are coagulated by the addition of chemicals, by vibration, electric current or heat.
Coal. A naturally occurring solid fuel which exists in the form of seams at varying depths below the earths surface. Formed by the arrested bacterial decay of vegetation that grew 40-300 million years ago, followed by chemical processes of condensation and polymerization under the influence of temperature, pressure and time. By these processes the differences between the original woody material and anthracite, the highest ranking coal, can be explained. As the rank increases the carbon content increases from about 50 to 95%, and the oxygen content decreases fro about 40 to 3%. The calorific value increases (average 3.3 x 107 JKg-1) through the range of coals: peat-lignites-bituminous-semi-bituminous and carbonaceous coals-to the anthracites.
The properties of the various coals in this ranking will vary considerably and many are used only for specific purposes.
Most deposits of coal were formed during the Carboniferous and Permian periods. More recent periods of coal formation occurred during the early Jurassic and Tertiary periods. Coal deposits occur in all the major continents; the leading producers include the USA, china, Russia, Poland, UK, South Africa, India, Australia, and West Germany. Coal is used as a fuel and in the chemical industry; by-products include coke and coal tar.
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