Bromide Cream

Add water phase to oil phase while stirring. Stir to cool. 

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Addition of silver nitrate to a solution of a bromide in nitric acid produces a cream-coloured precipitate of silver bromide, soluble in ammonia (but not so readily as silver chloride). The reaction may be used quantitatively, as for a chloride. 

Cyclopropyltriphenylphosphonium Bromide (5). The lactone salt is pyrolyzed by placing it in a round-bottom flask fitted with an adaptor attached to a vacuum source (aspirator is sufficient). The flask is heated (oil bath) to 180-190° for 48 hours. The residue is a virtual quantitative yield of the tan product, which may be crystallized from ethyl acetate giving cream crystals, mp 189-190°. An alternate setup is convenient if a drying pistol (Abderhalden) is available. The compound is placed in the pistol, which is then evacuated. Decalin (bp approx. 187°) is refluxed over the pistol to provide the heating source. The work-up is the same. 

In a similar way, a bromide and an iodide will react to produce either a cream precipitate of silver bromide (AgBr) or a yellow precipitate of silver iodide (Agl) (Figure 8.19). 

Bromide (Br) [in solution] Acidify with dilute nitric acid, then add aqueous silver nitrate Cream ppt. 

Calcium Lactobionate occurs as a white to cream-colored, free-flowing powder. It readily forms double salts, such as the chloride, bromide, and gluconate. It is anhydrous when obtained by spray-drying, or the dihydrate when obtained by crystallization. It is freely soluble in water, but insoluble in... 

This base (as the trihydrochloride) reacted with hexachloroplatinic(IV) acid to form the salt, XXXIV, in which the central nitrogen atom becomes asymmetric attempts to resolve it not unexpectedly failed as this group would almost certainly have very low, optical stability. The salt, XXXIV, when treated with silver salts, lost hydrogen chloride with the formation of the salt, XXXV. With potassium tetrachloroplatinate(II), the salt, XXXVI (X = Cl), was obtained and was more readily isolated after treatment in solution with sodium bromide or iodide as the cream-colored XXXVI (X = Br) or XXXVI (X = I), respectively. The free base reacted with aquopentamminocobaltic trichloride to give the... 

Cyclopentadiene reacts with mercuric cyanide in aqueous solution, giving the insoluble cream compound CsHsHgCN. Like the corresponding iodide (which is also cream) this compound is fairly stable in air, but does not melt sharply (62). By the reaction of indenyl lithium and mercuric chloride in dry ether, indenyl mercuric bromide (the bromine being... 

Citric acid Copper oxychloride Copper sulfate Cream of tartar Dextrin Dyestuffs Ethanol Ethyl bromide Ethyl chloride Ethyl ether Ethylene bromide Ferrous sulfate Formaldehyde Formic acid Furfural... 

In the case of the bromide, 1.61 g (0.5 mmole) of [Bu4N]Brin 5 mL of water is added. The copious precipitate is rinsed with water, collected, and air-dried, giving a crude yield of 2.50 g. Purification can be achieved by dissolving the solid in warm chloroform (20 mL), cooling, and adding diethyl ether (30 mL) to obtain 2.35 g of cream solid as small crystals (yield ca. 86%, based on gallium dissolved). 

Three of the halogens can be identified through precipitation reactions. Chlorine, bromine, and iodine react with silver nitrate, forming distinctive precipitates. Silver chloride is a white precipitate, silver bromide is a cream-colored precipitate, and silver iodide is a yellow precipitate. 

Bromides give a cream precipitate that is insoluble in dilute ammonia but dissolves in concentrated ammonia. Iodides give a yellow precipitate that is insoluble in concentrated ammonia. 

Typical Procedure tor Synthesis of Polymers. 4. A solution of BHB (3.18g, 10.0 mmole) and 25 mL of 2N aq. KOH solution was stirred under nitrogen at room temperature for wmin. A solution of a a -di-bromo-p-x] ene (2.20g, 8.33 mmole), benzyl bromide (0.57g, 3.33 mmole), and O.lg tetra-N-butylammonium bromide in 25 mL 1,2-di-chloroethane was added and the resulting mixture refluxed under nitrogen for 18h with vigorous stirring. The reaction mixture, wNch had gone from deep red to colorless, was then cooled to room temperature and 30 mL hexane was added. The resulting precipitate was then filtered and washed with 100 mL distiiled HoO, and dried under vacuum at 80°C for 18h to yield 4.0g (94%) of 4f as a cream colored solid. 

II) If a solution containing bromide ions (Br ) is added to silver nitrate solution, a cream precipitate is produced. If a solution containing iodide ions (I") is added to silver nitrate solution, a pale yellow precipitate is produced. What do you think these precipitates are Write an ionic equation for each precipitation reaction. 

The fizzing suggests that Z is probably H (aq). The cream coloured precipitate is probably silver bromide. Therefore, the unknown is a solution of hydrobromic acid. 

Cetylpyridinium bromide CAS 140-72-7 EINECS/ELINCS 205-428-3 Synonyms N-Cetylpyridinium bromide Hexadecylpyridine bromide Hexadecylpyridinium bromide Classification Quaternary ammonium compd. Empirical C2iH3sBrN Formula CieHaaCsHsNBr Properties Cream-colored waxy solid sol. in acetone, ethanol, chloroform m.w. 384.44 cationic... 

Hydroxycetyl hydroxyethyidimonium chloride Quaternium-51 Steartrimonium bromide antistat, hand creams Lactoyl methylsilanol elastinate antistat, hard-surface cleaners Disodium lauroamphodipropionate PEG-2 cocomonium chloride antistat, health prods. 

In small-scale preparation the quaternary ammonium compounds containing an alkyl chain are the most important. Cetrimide (Cetrimonium bromide, see Fig. 23.8) is used in a concentration of 0.5-2 % as emulsifier in creams. Quaternary ammonium compounds of this type are used from a concentration of 0.004 %. They also exhibit antiseptic and preservative properties. Notably benzalkonium chloride, as well as being a surfactant of the oil-in-water emulsifying type, is also important as a preservative in for example eye and nose drops. Catioiuc-active compounds are often incompatible with anionic substances such as sulfobituminose ammonium due to the risk of the formation of insoluble ion pairs. Since it is often difficult to estimate this risk, it is better to avoid these combinations. 

Bromides and iodides give cream and yellow precipitates of silver bromide and silver iodide (Figure 3.38), respectively ... 

This is a mixture consisting of tetradecyl ( 68%), dodecyl ( 22%) and hexadecyl ( 7%) trimethylammonium bromide. Solutions containing 0.1-1% cetrimide are used to dean skin, wounds and burns, in shampoos to remove scales of sebor-rhoea, and also in Cetavlon cream. 

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