Organic compounds carbon properties

Owing to several unique properties of carbon, such as its ability to form long chains, organic compounds—carbon compounds— come in virtually infinite variety. Organic chemists spend their time studying the ways that carbon reacts with itself and other compounds and... 

Rodd s Chemistry of Carbon Compounds, 2nd ed., Coffey, S., ed. Elsevier, Amsterdam, 1964-2001. A survey of all classes of organic compounds, giving properties and syntheses for many individual compounds consists of four volumes in 30 parts with supplements. 

In urea, two amine groups are attached to a carbonyl moiety. If the carbonyl is replaced by an imine function, one obtains guanidine. Guanidine is an instable compound with one of the highest basicities for organic compounds. Both properties are driven by the stabilization of the guanidinium cation by three amine functions connected to the central carbon atom. Due to the symmetric stmcture, the guanidinium cation is a very stable compound in combination with an anion... 

Several fluids have been used as supercritical solvents Table 11.4 shows the physical properties of several common SFs (95). The most common solvent is carbon dioxide because it has critical values that are easy to obtain (96), is nontoxic, becomes a gas at ambient temperatures and pressures, is inexpensive, and is mutually soluble with many organic compounds. Carbon dioxide can be obtained as a liquid from cylinders equipped with a dip tube. The cylinder headspace is often pressurized with 1500 psi of helium, which conveniently allows the liquid to be transferred to a delivery system. 

Substitution of fluorine for hydrogen in an organic compound has a profound influence on the compound s chemical and physical properties. Several factors that are characteristic of fluorine and that underHe the observed effects are the large electronegativity of fluorine, its small size, the low degree of polarizabiHty of the carbon—fluorine bond and the weak intermolecular forces. These effects are illustrated by the comparisons of properties of fluorocarbons to chlorocarbons and hydrocarbons in Tables 1 and 2. 

Vulcanization was first reported in 1839 with the discovery that heating natural mbber with sulfur and basic lead carbonate produced an improvement in physical properties (2). In 1906, aniline was the first organic compound found to have the abiUty to accelerate the reaction of sulfur with natural mbber (3). Various derivatives of aniline were soon developed which were less toxic and possessed increased acceleration activity. 

Pure carbon disulfide is a clear, colorless Hquid with a deHcate etherHke odor. A faint yellow color slowly develops upon exposure to sunlight. Low-grade commercial carbon disulfide may display some color and may have a strong, foul odor because of sulfurous impurities. Carbon disulfide is slightly miscible with water, but it is a good solvent for many organic compounds. Thermodynamic constants (1), vapor pressure (1,2), spectral transmission (3,4), and other properties (1,2,5—7) of carbon disulfide have been deterrnined. Principal properties are Hsted in Table 1. 

As a possible method of concentrating trace amounts of bioactive organic compounds occurring in the hydrosphere, adsorption properties of various compounds have been explored by employing hydrous metal oxides as the adsorbents. To date, a family of organophosphoms compounds and carbonic acids were adsorbed onto hydrous iron oxide, along with the adsoi ption of monosaccharides onto hydrous zirconium oxide. 

Most compounds in which carbon is the key element are classified as organic. Common examples of organic compounds include degreasing solvents, lubricants, and heating and motor fuels. This subsection highlights some of the more common characteristics of organics as they relate to hazards. Various relevant classes of organics are presented in terms of chemical behavior and physical properties. In order to facilitate the discussion to follow, a few basic definitions will be presented first. 

Modification techniques for activated carhon were used to increase the removal capacity by surface adsorption and to improve the selectivity to volatile organic compounds (VOCs). Modified activated carbons (MACs) were prepared by modifying the purified activated carbon with various acids or bases. The effects of adsorption capacity and modified contents on the textural properties of the MACs were investigated. Furthermore, VOC adsorption and desorption experiments were carried out to determine the relationship between the adsorption capacity and the chemical properties of the adsorbents. High adsorption capacity for the selected VOCs was obtained over lwt%-H3P04/AC (lwt%-PA/AC). As a result, MAC was found to be very effective for VOC removal by adsorption with the potential for repeated use through desorption by simple heat treatment. 

In electrocatalysis, the activated carbons, glassy carbon, and carbon black are the transitional forms used. Carbon black is the product of incomplete combustion or decomposition of organic compounds. The shape of its particles is close to spherical. They contain several carbon atom lattice fragments arranged without order. Various types of carbon black serve as substrates for metal catalysts, the properties of the carbon blacks themselves having a strong elfect on the catalytic activity of the combined catalysts thus obtained. 

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