Bromic acid preparation

Bromic acid is used as an oxidizing agent and also as intermediate in the preparation of dyes and pharmaceuticals. ... 

Bromic acid is prepared by adding sulfuric acid to barium bromate. 

Magnesium bromide is prepared by treating magnesium oxide with hydro-bromic acid and subsequent crystaUization above 0°C. The product is hexahydrate, MgBr2 6H20 ... 

Sodium bromide can be prepared by several methods. Pure salt can be made by neutralizing sodium hydroxide or sodium carbonate with hydro-bromic acid. The solution is evaporated for crystaUization ... 

Chloro-pentammino-chromic Bromide, [Cr(NH3)5Cl]Bra, has similar properties, and is prepared by addition of concentrated hydro-bromic acid to a cold aqueous solution of the chloride. 

Chloro-pentammino-cobaltic Bromide, [Co(NH3)5Cl]Bra, may be prepared from the chloride by treating a solution, which has been made slightly acid with dilute sulphuric acid, with well-cooled hydro-bromic acid. The precipitate formed is washed with dilute aqueous hydrogen bromide and then with alcohol. It may be formed also from the corresponding chloro-carbonate by precipitating from solution with concentrated hydrobromic acid. It crystallises in red oetahedra, and is more easily soluble than the chloride. 

The preparation oi the alkali bromides.—While V. Merz and W. Weith 2 found that metallic sodium reacts very slowly with bromine such that even after the two elements have been kept for 8 hrs. at 200°, the conversion of sodium into the bromide is but superficial potassium, caesium, and rubidium unite with bromine more quickly, forming the alkali bromide. The bromides are also formed when hydro-bromic acid is neutralized with the alkali hydroxide or carbonate, and the soln. evaporated. This method, for example, has been used for preparing rubidium bromide, RbBr. C. Chaubrie and N. N. Beketofi made a soln. of caesium bromide, CsBr, by the double decomposition of caesium sulphate, and barium bromide. P. Klein 3 made lithium bromide by digesting calcium bromide with lithium carbonate... 

Preparation of bromine by oxidizing hydro-bromic acid by manga-nese(IV) oxide Drawing of apparatus. Reaction equations. Required calculations. Tabulated data (b.p. of bromine, density, etc.) When the reaction mixture is heated, a brown bromine vapour condensing as a heavy reddish brown liquid evolves... 

Properties of Hydrobromic Acid. 1, See how the prepared hydro-bromic acid acts on a metal (magnesium or zinc) and on calcium carbonate. 

Prepare a little of a bromic acid solution. To do this, mix 2-3 drops of a saturated potassium bromate solution with 1-2 ml of a dilute sulphuric acid solution. Throw a minute iodine crystal into the solution, mix the test tube contents several times, decant the solution, and add several drops of an organic solvent to it. What is observed Write the equations of the reactions. Will bromine displace iodine from iodic acid ... 

In a 250 cc. round-bottom flask are placed 70 g. of hydro-bromic acid (48 per cent) and 22 g. of concentrated sulfuric acid. To this mixture are added 40 g. of lauryl alcohol (b. p. 188-192° at no mm.) and the mixture is then refluxed for five hours The bromide is isolated as described in the preparation of odyl bromide. The product is distilled under reduced pressure and is collected from 175-180° at 45 mm. The yield is 49 K (91 l r cent theory). 

It has been reported (Bruno Camerino, private communication) that, during the preparation of sodium nitromalonaldehyde monohydrate1 on a pilot-plant scale, two operators were so affected by the fumes evolved during the preparation that their immediate hospitalization was necessary. It was determined subsequently that hydrogen cyanide, up to approximately 1 g./kg. of muco-bromic acid utilized, was formed in the reaction mixture. It is essential that precautions specified in Note 1 of the procedure be followed carefully. 

The Dess-Manin periodinane ( DMP ) reagent, l,l,l-tris(acetyloxy)-l,l-dihydro-l,2-benziodoxol-3(lff)-one, has also been used in several complex syntheses for the oxidation of primary or secondary alcohols to aldehydes or ketones, respectively (e.g., M. Nakatsuka, 1990). It is prepared from 2-iodobenzoic acid by oxidation with bromic acid and acetylation (D. B. Dess, 1983). 

Gutbier1 prepared pure brom-platinic add by repeatedly evaporating the pure chloride with concentrated hydrobromie acid on the water-bath and then treating it similarly three or four times with hydro-bromic acid containing bromine. The residue, on being taken up with dilute hydrobromie add, yields a deep carmine-red solution. 

For the preparation of chlorides or bromides, the diazonium salt is decomposed with a solution of cuprous chloride or bromide in the corresponding halogen acid (Sandmeyer reaction). It is possible to prepare the aryl bromide from the diazonium chloride or sulfate. A variation Involves the use of copper powder and a mineral acid for the decomposition step (Gattermann reaction). Both procedures are illustrated by the syntheses of the isomeric bromotoluenes and chlorotoluenes. The usual conditions of the Sandmeyer reaction fail in the preparation of the chloro- and bromo-phenanthrenes. However, these compounds can be successfully obtained by the interaction of the diazonium compound with mercuric and potassium halides (Schwechten procedure). Another procedure for formation of aryl bromides involves treatment of the amine hydrobromide with nitrogen trioxide in the presence of excess 40% hydro-bromic acid. The Intermediate diazonium perbromide is then decomposed by heat. ... 

Several methods are available for the preparation of cis-bromoamminebis(ethylenediamine)cobalt(III) bromide. These include the reaction of frans-dibromobis(ethylene-diamine)cobalt(III) bromide with concentrated aqueous ammonia treatment of cfs-nitroamminebis(ethylenedi-amine)cobalt(III) bromide or a s-aquoamminebis(ethylene-diamine)cobalt(III) bromide with concentrated hydro-bromic acid and reaction of concentrated ammonium bromide with bis[bis(ethylenediamine)cobalt(III)-Ai-dihy-... 

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