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Organic compounds defined

Lipids (or fats) are a heterogeneous group of organic compounds defined by their solubility in nonpolar solvents such as chloroform, ether, and benzene and by their poor solubility in water. [Pg.365]

Modeling the elements discussed in this section is fairly similar to modeling organic compounds. This is primarily because d and/orbitals play a minor role in their chemistry. When d and/ orbitals do affect the chemistry, their effect is well defined and for the most part understood. [Pg.285]

What particularly seemed to excite Wohler and his mentor Berzelius about this experiment had very little to do with vitalism Berzelius was interested m cases m which two clearly different materials had the same elemental composition and he invented the term isomerism to define it The fact that an inorganic compound (ammonium cyanate) of molecular formula CH4N2O could be transformed into an organic compound (urea) of the same molecular formula had an important bearing on the concept of isomerism... [Pg.2]

At normal pressures (around atmospheric) and up to about 250°C (approaching the limit of thermal stability for most organic compounds), a volatile substance can be defined as one that can be vaporized by heat between ambient temperature (10 to 30°C) and 200 to 250°C. All other substances are nonvolatile. [Pg.413]

Nitration is defined in this article as the reaction between a nitration agent and an organic compound that results in one or more nitro (—NO2) groups becoming chemically bonded to an atom in this compound. Nitric acid is used as the nitrating agent to represent C-, 0-, and N-nitrations. O-nitrations result in esters. N-nitrations result in nitramines. [Pg.32]

Metalloid peroxides behave as covalent organic compounds and most ate insensitive to friction and impact but can decompose violentiy if heated rapidly. Most soHd metalloid peroxides have weU-defined melting points and the mote stable Hquid members can be distilled (Table 3). Some... [Pg.106]

In the United States, the reportable quantity of 1-propanol for spills under CERCLA "Superfund" is 100 Ib/d (45.4 kg/d). However, no reportable quantity is assigned for transport (43). The substance is on the list for atmospheric standards, as defined iu 40 CER 60.489 (47). The iatent of these standards is to require all newly constmcted, modified, and reconstmcted manufacturiug units to use the best demonstrated system of continuous emission reduction for equipment leaks of volatile organic compounds (47). 1-Propanol is also on the right-to-know regulations of the states of Connecticut,... [Pg.120]

Sulfation is defined as any process of introducing an SO group into an organic compound to produce the characteristic C—OSO configuration. Typically, sulfation of alcohols utilizes chlorosulfuric acid or sulfur trioxide reagents. Unlike the sulfonates, which show remarkable stability even after prolonged heat, sulfated products are unstable toward acid hydrolysis. Hence, alcohol sulfuric esters are immediately neutralized after sulfation in order to preserve a high sulfation yield. [Pg.74]

Many components of ships and marine stmctures are now coated in the shop under controlled conditions to reduce the amount of solvents released into the atmosphere, improve the quaUty of work, and reduce cost. Regulations designed to limit the release of volatile organic compounds into the air confine methods of shop apphcation to those having transfer efficiencies of 65%. Transfer efficiency is defined as the percent of the mass or volume of sohd coating that is actually deposited on the item being coated, and is calculated as... [Pg.366]

To define the position of an absorption, the NMR chart is calibrated and a reference point is used. In practice, a small amount of tetramethylsilane [TMS (CH )4Si] Is added to the sample so that a reference absorption peak is produced when the spectrum is run. TMS is used as reference for both l H and 13C measurements because it produces in both a single peak that occurs upfield of other absorptions normally found in organic compounds. The ]H and 13C spectra of methyl acetate in Figure 13.3 have the l MS reference peak indicated. [Pg.445]

The names of organic compounds have some system. Each functional group defines a family (for example, alcohols, amines) and a specific modifier is added to identify a particular example (for example, ethyl alcohol, ethyl amine). As an alternate naming system, the family may be named by a general identifying ending (for example, alcohol names end in -ol) and a particular example is indicated by an appropriate stem (ethyl alcohol would be ethanol). These naming systems are illustrated in Tables 18-1 and 18-11. [Pg.339]

The term fermentation was obtained from the Latin verb fervere which describes the action of yeast or malt on sugar or fruit extracts and grain. The boiling is due to the production of carbon dioxide bubbles from the aqueous phase under the anaerobic catabolism of carbohydrates in the fermentation media. The art of fermentation is defined as the chemical transformation of organic compounds with the aid of enzymes. The ability of yeast to make alcohol was known to the Babylonians and Sumerians before 6000 bc. The Egyptians discovered the generation of carbon dioxide by brewer s yeast in the preparation... [Pg.2]

The term plastic comes from the Greek word to form. It identifies many different plastic materials. Polymers, the basic ingredients used in practically all plastics, can be defined as high molecular weight organic compounds, synthetic or natural substance... [Pg.337]

To maximize safety and therapeutic efficacy, potential drugs are required to be highly specific for their protein target and orally bioavailable. In addition, for a drug candidate to reach the market, it must be patentably novel. A computational approach therefore needs to find novel compounds with well-defined pharmacological properties from the vast space of possible organic compounds ( chemical space ). [Pg.323]

The need for rapidly accessible estimation of toxicity has led to the development of software and other algorithms that will generate estimations of toxicity, usually for organic compounds [79] such methodology is termed an expert system, which has been defined [34] as any formalised system, not necessarily computer-based, which enables a user to obtain rational predictions about the toxicity of chemicals. Essentially, expert systems fall into two classes— those relying on statistical approaches and those based on explicit rules derived from human knowledge. [Pg.482]

A vitamin is defined as an organic compound that is required in the diet in small amounts for the maintenance of normal metabofic integrity. Deficiency causes a specific disease, which is cured or prevented only by restoring the vitamin to the diet (Table 45-1). However, vitamin D, which can be made in the skin after exposure to sunhght, and niacin, which can be formed from the essential amino acid tryptophan, do not stricdy conform to this definition. [Pg.481]

That the sweet and bitter responses are intimately associated is clear from the results of gustatory studies of all of the conformationally defined sugars and of other organic compounds. If a carbohydrate has any taste at all, this is invariably sweet, bitter-sweet, or bitter. Chemical modification may alter the taste of a sweet compound so that the product is bitter-sweet or bitter, and it is now generally agreed that the two basic tastes may each be a feature of a single compound. It appears, therefore, that the interactions of these polyfunctional stimulants involve two different sets of receptor sites, representing sweet and bitter modalities. ... [Pg.320]


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See also in sourсe #XX -- [ Pg.458 ]

See also in sourсe #XX -- [ Pg.458 ]

See also in sourсe #XX -- [ Pg.460 ]

See also in sourсe #XX -- [ Pg.364 ]

See also in sourсe #XX -- [ Pg.388 ]




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Compounding defined

Compounds, defined

Organization, defined

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