Bromate/bromide

Procedure. Place 80 mL of the arsenic/antimony solution in the titration cell of the spectrophotometer. Titrate with standard bromate/bromide solution at 326 nm taking an absorbance reading at least every 0.2 mL. From the curve obtained calculate the concentration of arsenic and antimony in the solution. 

Lithium acetate ammonium sulfate azide benzoate borate (meta-) bromate bromide carbonate chlorate chloride... 

Among the most important indirect methods of analysis which employ redox reactions are the bromination procedures for the determination of aromatic amines, phenols, and other compounds which undergo stoichiometric bromine substitution or addition. Bromine may be liberated quantitatively by the acidification of a bromate-bromide solution mixed with the sample. The excess, unreacted bromine can then be determined by reaction with iodide ions to liberate iodine, followed by titration of the iodine with sodium thiosulphate. An interesting extension of the bromination method employs 8-hydroxyquinoline (oxine) to effect a separation of a metal by solvent extraction or precipitation. The metal-oxine complex can then be determined by bromine substitution. 

Potassium bromate is an oxidizing reagent in bromate-bromide mixture for titrimetric analysis. It also is a bread- and Hour-improving agent. 

Potassium bromide is used to make photographic plates and papers and in engraving. Other uses are as a brominating agent in organic synthesis and in the bromate-bromide mixture in titrimetric analysis. In medicine potassium bromide is a sedative and anticonvulsant. 

As a matter of fact, continued Balard, when one strongly calcines the residue from the evaporation of the water from the salt works it loses its ability to liberate bromine in contact with chlorine. If one recalls that the hydro-bromates [bromides] I have examined, with the exception of that of magnesia, are not at all decomposed by heat, one will be tempted to suppose that the water of the salt works actually contained this compound. 

Several crops of crystals are now taken by evaporating the aqueous solution to the saturation point on a hot plate with stirring, then cooling. Each crop is dried for 2 hours at 100° and analyzed for unsaturation by the bromate-bromide titration method (Note 10). The first two crops usually total about 380 g. (based on 300 g. of sulfur trioxide), 49% yield, and are about 95% pure by titration. They may be further purified by one recrystallization from water, with about 80% recovery of 99+% pure salt. 

To the 50ml soln in the iodine flask, add 25ml of 0.2N standard potassium bromate-bromide soln (prepd as described in Method 605-1 of MIL-STD-286A), accurately measured to within 0.01ml... 

Add 25ml of CC14 and an accurately measured 10ml portion of 0.5N soln of K bromate-bromide. Moisten the stopper of the flask with a drop of 10% KI soln and add 5ml of 38% HC1, noting the time. Stopper the flask immediately,... 

Make a blank detn, using exactly the same volumes of bromate-bromide soln, glac AcOH... 

A)Aniline Content(minim 99.5%) is detd volumetrically by the potassium bromate-bromide method based on the following reaction ... 

Katalytische Reaktionen in der Spurenanalyse und Untersuchung ihrer Mechanismen III. Uber das Landoltsche Prinzip. IV. Kinetische Untersuchung der Bromat-Bromid-Ascorbinsaure-Reaktion auf Bromgrundlage. Mikrochim. Acta 1968, 455 und 473. 

Undecanoic acid, 32, 104 10-Undecynoic acid, 32, 104 Unsaturation, quantitative estimation by bromate-bromide titration method, 34, 86, 89 Urea, 30, 24 31, 11 Urea, I-(T -bromophenyl)-, 31, 8 1-(o-chlorophenyl)-2-thio-, 31, 21 1,1-dimethyl-, 32, 61 I-(P-phenetyl)-, 31,11... 

Bromate, bromide, chromate, iodate, iodide, nitrate, nitrite, thiocyanate 3-pm SAX or OT-Dionex AS5A particles electrostatically bound to the wall [170]... 

Method. Hydrochloric acid (5 ml) is added to 50 ml of the water solution in a 100 ml calibrated flask, an aliquot (1—3 ml) of the bromate—bromide solution is added and the flask is shaken. Following an allowed reaction time, the bromination is terminated by removing the excess of bromine by the addition of 1—2 drops of hydroxylamine reagent. The solution is then made up to the 100 ml mark with distilled water. Standards and blanks are treated in the same way as samples. 

Notes. Using 2 ml of bromate—bromide reagent and 5 min reaction time at room temperature, quantitative recoveries of organically bound mercury... 

Methods based on iodine titration with thiosulfate Iodide, being a weak reduc-tant, can react with an enormous variety of oxidants to liberate an equivalent quantity of I2 that can be titrated with thiosulfate. Such oxidants include peroxides, peroxy compounds, peroxydisulfate, ozone, iron(III), chromate, selenium (as Se03 ), silver(II) oxide, xenon trioxide, iodate, and bromate. Bromide can be determined by oxidizing it to bromine, followed by extraction and determination of the bromine... 

The first use of a bromate-bromide mixture as a source of bromine was by Koppescbaar, who devised the classical bromination method for phenol. The method is still in use today and has been applied to a wide variety of organic com-poimds. Three types of error can be recognized (7) oxidation of readily oxidized substances such as o- and p-aminophenols (2) precipitation of incompletely bromin-ated products, which occurs especially with parasubstituted compounds such as p-nitroaniline and p-iodoaniline and (5) replacement of certain groups such as —COOH, —CHO, or —SO3H by bromine. 

Make a blank determination, using 50ml of glac AcOH, and exactly the same vol of the potassium bromate-bromide soln 2.115(A-B)N... 

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