Reactions with Organic Substances

Reactions with Organic Nitrogen. Chlorine reacts readily with many organic nitrogen compounds fust as it does with ammonia. The organic amines, which have the group — NHa, —NH—, or —N= as part of their molecule, are very common. The elementary reaction with methylamine, CHsNHa, is typical 

The rate constant for this reaction, k = 10 - liter/mole-sec, is higher than that found for formation of NHaCl. Also, the formation of dichlorometh-ylamine, 

Morris, Kinetics of Reactions Between Aqueous Chlorine and Nitrogen Compounds in Principles and Applications of Water Chemisiry, S. D. Faust and J. V. Hunter, eds., John Wiley, New York, 1967. 

Tiihalomethane Formation, Trihalomethanes have the general form CHXa where X can be Cl, Br, or I. CHCI3, chloroform, is of particular interest because it is a suspected carcinogen. The health effects of the other species are unknown. A series of reactions demonstrating the basic steps by which chloroform may be produced during water treatment is as follows  

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Hypochlorous acid undergoes a variety of reactions with organic substances including addition, oxidation, C- and iV-chlorination, and ester formation. On an industrial scale, hypochlorous acid, generated m situ via chlorine hydrolysis, reacts with propylene forming primarily the a-propjlene chlorohydrin isomer. 

Reaction Velocity and Temperature.—Reactions with organic substances take place much more slowly than those which form the subject matter of a course of practical inorganic and analytical chemistry. The latter are nearly always ionic reactions, which proceed with immeasurable rapidity, but organic substances usually react much more slowly and therefore their preparation requires to be accelerated by increased temperature. A rise in the temperature of 10° doubles or trebles the velocity of most reactions. If the velocity at 20° is represented by v, then on the average that at 80° is v x 2 56. Consequently reactions will proceed in boiling alcohol about 250 times as fast as at-room temperature. 

This radical is among the strongest oxidizing agents found in aqueous systems and initiates a series of radical chain reactions with organic substances, resulting in mineralization of the sample to bicarbonate and orthophosphate. 

Reactions involving organic substances have some special features. Many of these substances are poorly soluble in aqueous solutions. Sometimes their solubilities can be raised by adding to the solution the salts of aromatic sulfonic acids with cations of the type [NHJ or alkali metal ions. These salts have a salting-in effect on poorly soluble organic substances. In many cases solutions in mixed or nonaque-ous solvents (e.g., methanol) are used. Suspensions of the organic substances in aqueous solutions are also useful for electrosynthesis. 

Whether or not the intermediate is a diradical, its reactions with organic bases are those appropriate for an electron deficient or electrophilic substance.80... 

Many accidents have been reported involving the preparation and the use of this compound. The compound is sensitive to heat and shock. Reactions with organic matter, finely divided metals and other readily oxidizable substances can be violent to explosive. It is a strong irritant to skin, eyes and mucous membranes. 

Blackwood and Bowden formulate the following mechanism for the ignition and burning reactions of blackpowder. First sulphur reacts with organic substances present in charcoal ... 

No other reaction products are observed. Like other reactions of organic substances with oxygen, the oxidation of ethylene is irreversible. 

In this case, the secondary reaction of organic substance dehydrogenation, conjugated with the primary reaction, represents oxidative dehydrogenation. This is the key moment... 

Raussell-Colom, J. A. and Serratosa, J.M. In Reactions of clavs with organic substances. In Chemistry of clays and clay minerals, edited by Newman, A.C.D. New York, NY John Wiley and Sons, 1987, p. 371. 

With all this specificity and the extraordinary power for providing greatly accelerated rates and a close connection to its own bio-organism, the electrochemist must ask if it is possible to take an enzyme out of its natural surroundings, put it on an electrode, have it exchange electrons with the electrode, and still retain its extraordinary activity and specificity for a reaction with a substance in solution that it is meant to catalyze. 

Datsko, V. G. (1940). Photometric investigation of the color reaction of sulfuric acid with organic substances in natural water. J. Appl. Chem. (SSR) 13, 384-389. 

Interactions of soil minerals with organic substances and microorganisms have a great impact on the formation and transformation of SRO Fe oxides (Schwertmann et al., 1986 Cornell and Schwertmann, 2003). Microorganisms may influence Fe transformation through reduction and oxidation reactions. Soil... 

At the end of the chemistry course the students are familiar with the fundamentals of chemical bonding, can differentiate between atomic bonds including polarised atomic bonds, ionic bonds and metallic bonds. They can relate the kind of bond to the property of the substance and are familiar with the structure and phenomenon of substances. They can also workout relationship between the structure and the reaction of organic substances. Chemistry imparts basic knowledge about major industries. Students also acquire knowledge about application of chemical science in other branches of production and spheres of life as well as about the inter-relationship between chemical industry and other industries. In the process they also realise the need of applying chemistry to well being of mankind. 

In water, short-lived singlet excited states of organic molecules are essentially immobile, while singlet oxygen can diffuse a limited distance (about 33 nm) prior to deactivation (Bayley et al., 1987). These intermediates can participate in chemical reactions at the site of absorption with molecules located in the near vicinity. Triplet excited states and free radicals of small organic molecules can diffuse several micrometers in water and have a larger potential to deactivate by chemical reactions with other substances in the formulation (Bayley et al., 1987). 

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