Cobalt, bromate

Cobalt Bromate, Co(Br03)2.6H20, is obtained by double decomposition of barium bromate with cobalt sulphate. On concentrating the filtered solution the salt crystallises out in red, octahedral crystals, which are readily decomposed by heat.1... 

Hypobromites, the salts of hypobromous acid, do not keep well because they gradually disproportionate to bromide and bromate. Solutions are best prepared as needed from bromine and alkafl with cooling. Because disproportionation is catalyzed by cobalt, nickel, and copper (70), these impurities should be avoided. SoHd alkaline earth hypobromites, or more properly, bromide hypobromites such as calcium bromide hypobromite [67530-61 CaBr(OBr), have been known for many years, but the pure crystalline hydrates sodium hypobromite pentahydrate [13824-96-9] NaOBr 5H20, and potassium hypobromite tribydrate [13824-97-0], KOBr 3H20, were not described until 1952 (71). Hypobromites are strong bleaching agents, similar to hypochlorites. 

The cobalt complex is usually formed in a hot acetate-acetic acid medium. After the formation of the cobalt colour, hydrochloric acid or nitric acid is added to decompose the complexes of most of the other heavy metals present. Iron, copper, cerium(IV), chromium(III and VI), nickel, vanadyl vanadium, and copper interfere when present in appreciable quantities. Excess of the reagent minimises the interference of iron(II) iron(III) can be removed by diethyl ether extraction from a hydrochloric acid solution. Most of the interferences can be eliminated by treatment with potassium bromate, followed by the addition of an alkali fluoride. Cobalt may also be isolated by dithizone extraction from a basic medium after copper has been removed (if necessary) from acidic solution. An alumina column may also be used to adsorb the cobalt nitroso-R-chelate anion in the presence of perchloric acid, the other elements are eluted with warm 1M nitric acid, and finally the cobalt complex with 1M sulphuric acid, and the absorbance measured at 500 nm. 

Write formulas for each of the following compounds (a) barium bromide, (b) copper(Il) bromate, and (c) cobalt(lll) fluoride. 

Cobalt Copper Acetylene, hydrazinium nitrate, oxidants Acetylene and alkynes, ammonium nitrate, azides, bromates, chlorates, iodates, chlorine, ethylene oxide, fluorine, peroxides, hydrogen sulfide, hydrazinium nitrate... 

Ammonium Bichromote(Dichromote). See under Chromates, Bichromates, etc Ammonium Borate. See under Borates Ammonium Bromate. See under Bromates Ammonium Carbamates. See under Carbamate Ammonium Carbonate. See under Carbonates Ammonium Chlorate. See under Chlorates Ammonium Chloride. See under Chlorides Ammonium Chromate. See under Chromates Ammonium Cobaltic Hexanitrate. See Ammonium Hexanitrocobaltate... 

Tetra(3-aminopropanethiolato)trimercury perchlorate, 3576 Tetraamminebis(dinitrogen)osmium(II) perchlorate, 4065 Tetraamminebis(5-nitro-2//-tetrazolato)cobalt( 1 I ) perchlorate, 0966 Tetraammine-2,3-butanediimineruthenium(III) perchlorate, 1788 Tetraamminecadmium permanganate, 3950 Tetraamminecopper(II) azide, 4271 Tetraamminecopper(II) bromate, 0263b Tetraamminecopper(II) nitrate, 4270 Tetraamminecopper(II) nitrite, 4269 Tetraamminecopper(II) sulfate, 4268... 

Action of heat Potassium bromate on heating evolves oxygen and a bromide remains. Sodium and calcium bromates behave similarly, but cobalt, zinc, and other similar metallic bromates evolve oxygen and bromine, and leave an oxide. 

Barium bromate oo Ba(Br03)2 H20 -15.9 Cobaltous bromide aq CoBra +18.4... 

Under given conditions, passivity is attained with increasing readiness in the order iron, cobalt, nickel iron is much more difficult to render passive than is nickel in a particular electrolyte. Metals of the iron group become passive more readily in alkaline than in acid solutions, and oxidizing agents, e.g., iodate, bromate, chlorate, chromate and nitrate, favor passivity chloride ions markedly inhibit the onset of passivity. Increase of temperature increases the c.d. required for the anode to become passive under a given set of conditions. 

In various sections above we have discussed the simple kinetic schemes, some of which have been applied to experimental data on annealing of recoil atoms. For example, it was thought at first (91) that the kinetics of cobaltic trisethylenediamine annealing obeyed a linear combination of twm unimolecular terms. Further analysis (53) has shown that this interpretation was probably in error, and also that the potassium chromate and bromate data could not be fitted by a small number of simple exponential terms. We have also attempted to fit the potassium bromate and cobaltic trisethylenediamine data by the error-function expression suggested by Fletcher and Brown (10, 27), see Section Bid above, and although the fit is reasonably good over portions of the isothermal curves, the point of inflection near the time-zero axis in the error-function expression is not observed experimentally. 

ACTIVATED CARBON or ACTIVATED CHARCOAL (64365-11-3) Dust or powder reacts, possibly violently, with strong oxidizers, ammonium perchlorate, bromates, bromine trifluoride, chlorates, cobalt nitrate, iodates, strong acids, halogens, lead chlorite, nitrates, nitric acid, oxides, perchlorates, peroxides, peroxyformic acid, sulfates, sodium sulfite, unsaturated oils. Forms heat- and impact-sensitive materials with ammonium perchlorate. Incompatible with many compounds, including triethylenediamine, palladium, potassium dioxide, potassium peroxide, silver nitrate, sodium chlorite. 

ESTANO (Spanish) (7440-31-5) Finely divided material is combustible and forms explosive mixture with air. Contact with moisture in air forms tin dioxide. Violent reaction with strong acids, strong oxidizers, ammonium perchlorate, ammonium nitrate, bis-o-azido benzoyl peroxide, bromates, bromine, bromine pentafluoride, bromine trifluoride, bromine azide, cadmium, carbon tetrachloride, chlorine, chlorine monofluoride, chlorine nitrate, chlorine pentafluoride, chlorites, copper(II) nitrate, fluorine, hydriodic acid, dimethylarsinic acid, ni-trosyl fluoride, oxygen difluoride, perchlorates, perchloroethylene, potassium dioxide, phosphorus pentoxide, sulfur, sulfur dichloride. Reacts with alkalis, forming flammable hydrogen gas. Incompatible with arsenic compounds, azochloramide, benzene diazonium-4-sulfonate, benzyl chloride, chloric acid, cobalt chloride, copper oxide, 3,3 -dichloro-4,4 -diamin-odiphenylmethane, hexafluorobenzene, hydrazinium nitrate, glicidol, iodine heptafluoride, iodine monochloride, iodine pentafluoride, lead monoxide, mercuric oxide, nitryl fluoride, peroxyformic acid, phosphorus, phosphorus trichloride, tellurium, turpentine, sodium acetylide, sodium peroxide, titanium dioxide. Contact with acetaldehyde may cause polymerization. May form explosive compounds with hexachloroethane, pentachloroethane, picric acid, potassium iodate, potassium peroxide, 2,4,6-trinitrobenzene-1,3,5-triol. 

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