Oxides of chlorine, bromine and iodine

The oxides of chlorine, bromine and iodine are listed in Table 16-2. Oxides of fluorine were discussed in Chapter 14 (page 412) while these were called oxygen fluorides because of the greater electronegativity of fluorine,... 

The valency Of chlorine, bromine, and iodine.—Compounds are known in which the three halogens act as uni-, ter-, quinque-, or septa-valent elements. Usually, however, these elements are univalent. In chlorine dioxide, C102, the chlorine is bi- or quadri-valent.19 In M. Berthelot s hydrogen perchloride, HC13, the chlorine is probably tervalent, and R. Meldola (1888) showed that the oxygen in the hydrochloride of methyl oxide is best regarded as quadrivalent, the chlorine tervalent thus, (CH3)2 0 Cl.H. Iodine also appears to be tervalent in the so-called iodonium compounds. 

Add a potassium permanganate solution to one of an iron(II) salt acidified with sulphuric acid. What happens Write the equations of the reactions of an iron(II) salt with potassium permanganate and with potassium dichromate. Will an iron(ll) salt be oxidized by chlorine, bromine, and iodine water (see Appendix 1, Table 21) How do iron(II) salts react with hydrogen sulphide and ammonium sulphide ... 

These oxidation processes also dominate in the chemistry of air pollution, where the occurrence of harmful levels of O3 and acidic aerosols depends on the relative and absolute levels of urban emissions of NO, CO, RH, and SO2. In the marine and polar troposphere, reactive compounds of chlorine, bromine, and iodine provide a small but significant additional pathway for oxidation besides OH, as discussed by von Glasow and Cmtzen (see Chapter 4.02). 

Chapter 16 Oxides and oxofluorides of chlorine, bromine and iodine 483... 

Russel [142] developed a method based on the conversion of chlorine, bromine and iodine ions into the corresponding halogenated ethanols by reaction with ethylene oxide. Belcher et al. [143] offer a method for determining trace amounts of chloride ions, based on reaction with mercury phenylnitrate to give phenylmercury chloride, which is chromatographed with flame-ionization detection. 

The Beiktein or copper wire test clearly indicates the presence of chlorine, bromine and iodine and was developed by Friedrich Konrad Beiktein (1838— 1906) (Vogel, 1978). It is widely used to identify PVC. A clean, copper wire 30—40 cm long with a cork, or other heat-insulating material, at one end as an insulating handle, is heated with a Bunsen burner or other flame source until the flame k colourless to clean it of residual impurities and to develop a coating of copper (U) oxide. The hot copper is then placed in contact with the... 

All of the halogens form stable compounds in which the element is in the -1 oxidation state. In fluorine compounds, this is the only oxidation state. Chlorine, bromine, and iodine also have compounds in which the halogen is in one of the positive oxidation states +1, +3, +5, or +7. The higher positive oxidation states (> +1) are due to the involvement of d orbitals in bonding. 

Elemental and oxidized halogens. Chlorine, bromine and iodine, when added to a solution of Ag", form the corresponding halide and halate, the hypohalite being an intermediate product ... 

KrF+ AsF/, KrF+ SbF/, and KrF+ Sb2F, are moderately stable at room temperature. The KrF+ cation ranks as the most powerful chemical oxidizer known (120) and is capable of oxidizing gaseous xenon to XeF/, gaseous oxygen to O2, NF to NF, and chlorine, bromine, and iodine pentafluorides to... 

Tin does not react directly with nitrogen, hydrogen, carbon dioxide, or gaseous ammonia. Sulfur dioxide, when moist, attacks tin. Chlorine, bromine, and iodine readily react with tin with fluorine, the action is slow at room temperature. The halogen acids attack tin, particularly when hot and concentrated. Hot sulfuric acid dissolves tin, especially in the presence of oxidizers. Although cold nitric acid attacks tin only slowly, hot concentrated nitric acid converts it to an insoluble hydrated stannic oxide. Sulfurous, chlorosulfuric, and pyrosulfiiric acids react rapidly with tin. Phosphoric acid dissolves tin less readily than the other mineral acids. Organic acids such as lactic, citric, tartaric, and oxaUc attack tin slowly in the presence of air or oxidizing substances. 

Additional publications from Sanford et al. describe the full exploration of palladium-catalyzed chelate-directed chlorination, bromination, and iodination of arenes using N-halosuccinimides as the terminal oxidant <06T11483>. Moreover, an electrophilic fluorination of dihalopyridine-4-carboxaldehydes was reported by Shin et al. <06JFC755>. This was accomplished via transmetalation of the bromo derivative, followed by treatment with A-fluorobenzenesulfinimide as the source of electrophilic fluorine. 

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