Bromine monochloride

With bromine monochloride at 0°C in a variety of solvents, 1 was converted into addition products, the product distribution being a function of solvent. A change in halogenating agent also altered the product ratio. (Scheme 4) Nucleophilic displacement reactions between these products and silver fluoride was found to cause preferential bromine substitution (83G149). 

Self-Test 9.10A Bromine monochloride, BrCI, decomposes into bromine and chlorine and reaches the equilibrium 2 BrCI(g) Br2(g) + Cl2(g), for which K = 32 at 500. K. If initially pure BrCI is present at a concentration of 3.30 mbar, what is its partial pressure in the mixture at equilibrium ... 

V-9.1 Bromine Monochloride, 191 V-9.2 Iodine Monochloride, 191 V-9.3 Iodine Monobromide, 191 V-10 Alkali Iodides, 192... 

The halogenation of a wide variety of aromatic compounds proceeds readily in the presence of ferric chloride, aluminum chloride, and related Friedel-Crafts catalysts. Halogenating agents generally used are elemental chlorine, bromine, or iodine and interhalogen compounds (such as iodine monochloride, bromine monochloride, etc.). These reactions were reviewed554 and are outside the scope of the present discussion. 

Chlorine monofluoride, CIF Chlorine trifluoride, CIF3 Bromine monofluoride, BrF Bromine trifluoride, BrF3 Bromine pentafluoride, BrF5 Bromine monochloride, BrCI Iodine trifluoride, IF3 Iodine pentafluoride, IF5 Iodine heptafluoride, IF7 Iodine monobromide, IBr Iodine monochloride, ICI Iodine pentabromide, IBr5 Iodine tribromide, IBr3 Iodine trichloride, ICI3 Iodine pentachloride, ICI5... 

Bromine monochloride is also prepared by the combination of the elements... 

Chlorine water The addition of this reagent dropwise to a solution of a bromide liberates free bromine, which colours the solution orange-red if carbon disulphide, chloroform or carbon tetrachloride (2 ml) is added and the liquid shaken, the bromine dissolves in the solvent (see The Distribution Law, Section 1.45) and, after allowing to stand, forms a reddish-brown solution below the colourless aqueous layer. With excess chlorine water, the bromine is converted into yellow bromine monochloride or into colourless hypobromous or bromic acid, and a pale-yellow or colourless solution results (difference from iodide). 

Bromide and iodide in the presence of each other and of chloride The presence of a chloride does not interfere with the reactions described below. To the soda extract, strongly acidified with dilute hydrochloric acid add 1-2 drops of chlorine water (the solution obtained by carefully acidifying a dilute solution of sodium hypochlorite with dilute hydrochloric acid may also be used) and 2-3 ml chloroform or carbon tetrachloride shake a violet colour indicates iodide. Continue the addition of chlorine water or of acidified sodium hypochlorite solution drop by drop to oxidize the iodine to iodate and shake after each addition. The violet colour will disappear, and a reddish-brown colouration of the chloroform or carbon tetrachloride, due to dissolved bromine (and/or bromine monochloride, BrCl), will be obtained if a bromide is present. If iodide alone is present, the solution will be colourless after the violet colour has disappeared. 

Chlorine monofluoride may be prepared by direct interaction at 220 to 250°C and it is readily freed from C1F3 by distillation, but it is best prepared by interaction of Cl2 and C1F3 at 250 to 350°C. Bromine monofluoride also results on direct reaction of Br2 with F2, but it has never been obtained in high purity because of its ready disproportionation. Iodine monochloride is obtained as brownish-red tablets (J3 form) by treating liquid chlorine with solid iodine in stoichiometric amount, and cooling to solidify the liquid product. It readily transforms to the a form, ruby-red needles. Bromine monochloride is prone to dissociation ... 

Intermediate K. When significant amounts of both reactant and product are present at equilibrium, K has an intermediate value, as when bromine monochloride breaks down to its elements at 1000 K ... 

The high instability of bromine monochloride (the heat of formation of which has been estimated as 0.3 kcal.mole ) provides some difficulty in studying its reactions. Nonetheless, the rate of addition of mixtures of chlorine and bromine (with the total concentration of halogen constant) to c/s-cinnamic acid in carbon tetrachloride-acetic acid mixtures was greatest when [Br2]/[Cl-i] was unity . The kinetic form of the reaction was the same as that for the other interhalogens and for bromine, but not for chlorine. The possible intervention of bromine monochloride in the reaction of allyl trimethylammonium perchlorate with hypobromous acid in aqueous acid has also been reported here, the kinetics were . 

Synonyms Bromine monochloride Bromochloride Chlorine bromide... 

Lithium/Thionyl Chloride with Bromine Monochloride (BCX)... 

Photo-oxidation instead of wet-chemical oxidation is often considered an attractive method because of the very low blanks. However, irradiation with UV light does not seem to ensure complete recovery of mercury from organically assodated and related species. Reduced signals have even been observed following extended irradiation times (Gerwinski et al., 19%) which might indicate the formation of compounds with decomposition products from which Hg cannot be liberated by reduction with Sn. Therefore, to determine true total mercury concentrations, UV irradiation must be followed by wet-chemical oxidation. For samples with DOC concentrations of > 25 mg/L, an initial preoxidation by UV-irradiation was found necessary to ensure total oxidation of DOC and accurate determination of Hgx by the bromine monochloride method (Olson et al, 1997). 

For example, consider the interhalogen, bromine monochloride, BrCl. The compound is composed of two non-metals and hence likely to be covalent. It is a polar molecule with a partial negative charge on the chlorine and a partial positive charge on the bromine. There is no hydrogen atom present so dipole—dipole forces and London (dispersion) forces are operating between the molecules. 

Chlorine (CI2), Bromine Monochloride (BrCl), Bromine (Br2), Iodine (I2)... 

Chlorine CI2, and bromine monochloride BrCl are formed in the reactions of CIONO2, Br0N02, HCl, HBr, HOCl, HOBr in the heterogeneous reaction in the polar stratospheric clouds (see Sect. 6.5), and their photolyses play an important role in the chain reactions of the ozone hole formation. In the troposphere, CI2 is known to be produced in the heterogeneous reactions on sea salts, but observational data is still limited. Bromine Bra is known to be produced by the heterogeneous chain reactions in the tropospheric ozone destruction in the arctic region. Meanwhile, iodine I2 is released from sea weeds in coastal regions. 

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