Barium nitrite, decomposition

Barium nitrite [13465-94-6] Ba(N02)2, crystallines from aqueous solution as barium nitrite monohydrate [7787-38-4], Ba(N02)2 H2O, which has yellowish hexagonal crystals, sp gr 3.173, solubihty 54.8 g Ba(NO2)2/100 g H2O at 0°C, 319 g at 100°C. The monohydrate loses its water of crystallization at 116°C. Anhydrous barium nitrite, sp gr 3.234, melts at 267°C and decomposes at 270 °C into BaO, NO, and N2. Barium nitrite may be prepared by crystallization from a solution of equivalent quantities of barium chloride and sodium nitrite, by thermal decomposition of barium nitrate in an atmosphere of NO, or by treating barium hydroxide or barium carbonate with the gaseous oxidiation products of ammonia. It has been used in diazotization reactions. 

In an atmosphere of nitric oxide, thermal decomposition produces barium nitrite, Ba(N02)2. Reactions with soluble metal sulfates or sulfuric acid yield barium sulfate. Many insoluble barium salts, such as the carbonate, oxalate and phosphate of the metal, are precipitated by similar double decomposition reactions. Ba(N03)2 is an oxidizer and reacts vigorously with common reducing agents. The solid powder, when mixed with many other metals such as aluminum or zinc in their finely divided form, or combined with alloys such as... 

G. Canneri found that the treatment of a suspension of thallium sesquioxide in water with liquid nitrous anhydride, and subsequent evaporation of the soln., even in the cold under reduced press., yields, not thallic nitrite, but thallous nitrate. The latter is also obtained when soln. of thallic sulphate and barium nitrite are mixed in the cold, and the resulting liquid evaporated at low temp. That thallic nitrite is capable of existence in soln., although it cannot be obtained in the solid condition, is shown by the analyses and properties of the soln. The treatment of an aq. soln. of thallic nitrite with alcohol yields a precipitate of the sequioxide. In ethereal soln., thallic nitrite is far more stable, and the salt separates in the solid state on evaporation of the solvent it could not, however, be analyzed directly. Decomposition of thallic nitrite, with formation of thallous nitrate, takes place solely in accordance with the equation T1 (N02)3->TlN03+N2Os, neither intermediate reduction products nor thallous-thallic complex compounds being formed. 

Nickel Nitrite, Ni(N02)2.—A solution of nickel nitrite is obtained by double decomposition of nickel sulphate and barium nitrite, but the salt itself has not been isolated. It yields a stable double salt with... 

BARIUM SULFIDE (21109-95-5) BaS Flammable solid. Oxidizes in dry air. Contact with acid, acid fumes, moisture, steam, or moist air causes decomposition with the formation of toxic and flammable hydrogen sulfide gas. Evolved gas can form explosive mixtures with air and may cause spontaneous ignition or explosion. Violent reaction with strong oxidizers, calcium chlorate calcium nitrate chlorine dioxide phosphorus(V) oxide strontium chlorate strontium nitrate. Incompatible with lead dioxide, potassium chlorate, potassium nitrite may explode at elevated temperatures. On small fires, use smothering quantities of dry chemical powder, dry clay, dry groimd limestone (CaCOj), dry soda ash,dry sand or approved Class D extinguishers, do not use water, foam, or hydrous agents. 

Barium azide may be obtained by any of the methods described for calcium azide. When precipitating the aqueous solution, acetone should be preferred as it yields a coarser product [132] which is less likely to contain impurities. The salt has also been synthesized with hydrazine and nitrite 3.5 g barium hydroxide and 200 ml aqueous hydrazine (5% w/w) were cooled with ice and 15 g ethyl nitrite added dropwise with stirring. The next day, excess hydroxide was removed with CO2 the filtrate yielded 8 g barium azide (30% of the theoretical yield) [49]. Small samples of barium azide have also been made according to the Wislicenus process the intermediate amide formed at 260-290°C and the azide at 140-175°C [85], which is, however, already within the range of thermal decomposition. 

Histidine hydrochloride (2 g.) is suspended in concentrated hydrochloric acid and slowly treated with silver nitrite (3 g.). After removal of excess nitrous acid and silver chloride, the liquid is concentrated to a sirup, which is taken up in alcohol, treated with an excess of alcoholic trimethylamine solution, and kept at 80° for 8 hours. After removal of the alcohol the product is precipitated with phosphotungstic acid. The phosphotungstate is decomposed with barium hydroxide in the usual manner, and the solution of the base thus obtained is strongly concentrated to remove trimethylamine, treated with hydrochloric acid, and the resulting chloride is taken up in alcohol and precipitated with chloroplatinic acid. It is finally converted into the chloroaurate, m.p. 183° with decomposition (14). 

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