Ferrous bromide

Bromiir, n. (-ous) bromide. (Used for a metal in its lower valence, as Eiaenbromur, ferrous bromide.)... 

Ferro-, ferrous, ferro-, ferroeo-, iron(II). -ammonsulfat, n. ammonium ferrous sulfate, -azetat, n. ferrous acetate, iron(II) acetate, -bor, n. ferroboron. -bromid, n. ferrous bromide, iron(II) bromide, -chlorid, n. ferrous chloride, iron(II) chloride, -chrom, n. ferrochrome, ferrochromium. 

Ammino-ferrous Bromides.—Ferrous bromide readily absorbs ammonia at low temperatures with formation of hexammino-ferrous bromide, [Fe(NH3)6]Br2. The substance is a white powder which, on rise of temperature, dissociates, giving the diammine, [Fe(NH3)2]Br2, at... 

Henry prepared sodium and potassium bromides by boiling ferrous bromide respectively with potassium or sodium carbonate until the precipitate is brown the clear liquid was then filtered and evaporated. J. Knobloch recommended treating a mixture of ferrous bromide with milk of lime, and then with potassium sulphate if potassium bromide is desired, or with Glauber s salt if sodium bromide is to be made. The mixture is then to be boiled, the precipitated iron oxide filtered off, and the soln. evaporated, for cubic crystals of potassium bromide. This is the principle of the method employed for manufacturing potassium bromide on a large scale ... 

The calcium bromide and ferrous bromide towers are frequently refilled if much product is to be prepared. 

Tribromopyridine gave a mixture of 2,3,4,5-tetrabromo- and 2,3,4,5,6-pentabromopyridine. The bromination of 2,6-dibromopyridine at various temperatures between 450° and 550°, in the presence or absence of ferrous bromide or cuprous bromide, has been studied.391 Scheme XI illustrates some of the results obtained. At... 

Three years later Baxter4 made another determination of the atomic weight of iron, analysing anhydrous ferrous bromide for the purpose. The salt was sublimed in a porcelain tube, which introduced a little sodium bromide into it due allowance was made for this source of error, and the following results obtained (Ag=107-880, Br =79 -916) —... 

Baxter and Thorvaldson 2 extended the preceding investigation by making a number of analyses of ferrous bromide prepared from meteoric iron. The results were as follow —... 

Both the aqueous and alcoholic solutions of ferrous bromide absorb nitric oxide,2 the limit of absorption being reached with one molecule of NO to each atom of iron. The compound FeBr2.NO has not been isolated. 

Anhydrous ferrous bromide absorbs dry nitrogen peroxide, yielding a stable compound, 4FeBr2.N02, which retains its nitrogen peroxide even in vacuo. In the presence of moisture more peroxide is absorbed, but the reaction is complex, bromine being evolved.3... 

Ferrous bromide unites with ethylene 4 and acetylene. 

The solubility of ferrous bromide in water is given as follows — 5... 

Heating ferrous chloride in a current of dry ammonia,1 the optimum temperature for the reaction being 480° C.2 Ferrous bromide may be used instead of the chloride.3... 

Iron(If) bromide, FeBr2 (ferrous bromide), is a pale yellow/brown hygroscopic solid soluble in water and donor organic solvents. It may be prepared from iron and bromine at 200 °C, or iron and HBr in methanol, hydrobromination of iron(III) oxide at 200-350 °C, or dehydration of [FeBr2(H20)4]. The anhydrous compound is readily purified from FeBr3 by sublimation under nitrogen or in vacuo. It... 

Vapor phase bromination of bromopyrazine (feed ratios 1 1) at 425-625° with water as a diluent gave dibromopyrazines, and increased feed ratios favored formation of tribromopyrazine (768). The reaction of2-bromopyrazine (0.10 mol) and bromine (0.11 mol) with a trace of phosphorus tribromide and ferrous bromide at 95° formed 2,3-dibromopyrazine (797). Bromination of 2-bromo-3-chloromethylpyrazine in carbon tetrachloride has been claimed to give 2,5-dibromo-3-chloromethylpyrazine, 2,6-dibromo-3-chloromethylpyrazine, and 2,5,6-tribromo-3-chloromethylpyrazine (688). 

The introduction of bromine can be essentially facilitated by the use of a so-called bromine carrier. As such, the bromides of metalloids, or metals, are used (1) either in the already prepared condition, or (2) they can be generated from their elements in the reaction. To the first class belong ferric bromide and aluminium bromide. The action of ferric bromide depends on the fact that on being reduced to ferrous bromide, it yields bromine in statu nascendi ... 

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