Chlorine radicals physical properties

Physical properties of hexachloroethane are Hsted in Table 11. Hexachloroethane is thermally cracked in the gaseous phase at 400—500°C to give tetrachloroethylene, carbon tetrachloride, and chlorine (140). The thermal decomposition may occur by means of radical-chain mechanism involving -C,C1 -C1, or CCl radicals. The decomposition is inhibited by traces of nitric oxide. Powdered 2inc reacts violentiy with hexachloroethane in alcohoHc solutions to give the metal chloride and tetrachloroethylene aluminum gives a less violent reaction (141). Hexachloroethane is unreactive with aqueous alkali and acid at moderate temperatures. However, when heated with soHd caustic above 200°C or with alcohoHc alkaHs at 100°C, decomposition to oxaHc acid takes place. 

The first step in preparing the very useful elastomer Hypalon involves treating a mixture of long-chain alkanes, H(CH2) H, where n =50-200, with sulfuryl chloride (S02C 2) in the presence of substances that can initiate radical-chain chlorination, as described in Section 4-5B. The product molecules contain many C-CI bonds and a few C-S02-Cl bonds, the latter of which are subsequently used in a curing step to improve the physical properties. How can the chain mechanism for chlorination with S02CI2 be modified to account for the formation of C-S02-Cl bonds ... 

Exercise 29-6 Radical-induced chlorination of polyethene in the presence of sulfur dioxide produces a polymer with many chlorine and a few sulfonyl chlo-- ide (—S02CI) groups, substituted more or less randomly along the chains. Write suitable mechanisms for these substitution reactions. What kind of physical properties would you expect the chlorosulfonated polymer to have if substitution is carried to the point of having one substituent group to every 25 to 100 CH2 groups How may this polymer be cross-linked (A useful product of this general type is marketed under the name of Hypalon.)... 

The combination of chemical and electrical treatment has been reported (31). Compounds, used in this application, are chemicals that have a property of liberating free chlorine radicals, such as chlorinated oils, chlorocosane, chloramines, toluene, and hydrochlorites. Effects of chemicals on the breaking of petroleum have been investigated. The most general explanation is that the coalescence of the dispersed phase in emulsion resulted from both chemical reaction and physical effects of the chemicals, change the interfacial properties and facilitating droplet-droplet coalescence. 

Because there are only primary and tertiary hydrogen atoms in 146, the relative percent of 149 is 9/10 x 1 and the relative percent of 93 is 9/10 x 5.2. The percent of 149 is therefore 0.9/(0.9 -t- 0.52) = 0.9/1.42 = 0.63 x 100 = 63%. The percentage of 93 is 0.52/(0.9 -i- 0.52) = 0.52/1.42 = 0.37 x 100 = 37%. The mixture of two chlorinated products is predicted to be a ratio of 63 37, 63% of 149 and 37% of 93. These alkyl chlorides are isomers, and they should have different but quite similar physical properties, so they may be difficult to separate. The difference in rate between primary and tertiary is only a factor of five, so reaction is not selective for one product because the radical intermediate is not very selective for one type of hydrogen atom over another. In other words, there will be a mixture and no product is favored to a great extent over the other. 

Each isomer has its individual set of physical and chemical properties however, these properties are similar (Table 6). The fundamental chemical reactions for pentanes are sulfonation to form sulfonic acids, chlorination to form chlorides, nitration to form nitropentanes, oxidation to form various compounds, and cracking to form free radicals. Many of these reactions are used to produce intermediates for the manufacture of industrial chemicals. Generally the reactivity increases from a primary to a secondary to a tertiary hydrogen (37). Other properties available but not Hsted are given in equations for heat capacity and viscosity (34), and saturated Hquid density (36). 

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