Barium acetate, decomposition

Barium acetate converts to barium carbonate when heated in air at elevated temperatures. Reaction with sulfuric acid gives harium sulfate with hydrochloric acid and nitric acid, the chloride and nitrate salts are obtained after evaporation of the solutions. It undergoes double decomposition reactions with salts of several metals. For example, it forms ferrous acetate when treated with ferrous sulfate solution and mercurous acetate when mixed with mercurous nitrate solution acidified with nitric acid. It reacts with oxahc acid forming barium oxalate. 

In addition, the decomposition of the carboxyl groups was studied by measuring the carboxylate concentrations in the chars after pyrolysis. The technique to determine the carboxyl group content is outlined in detail elsewhere (11), and is based on the work of Schafer (17). There are three basic steps involved acid washing, exchange with barium acetate and determination of the extent of exchange. 

Barium ditungstate, BaO.2WO3.HoO, is obtained according to Lefort by double decomposition from solutions of sodium ditungstate and barium acetate, as a white amorphous precipitate, slightly soluble in water. The existence of this compound has been disputed. ... 

This reaction has been optimized by the application of an active and reliable catalyst prepared by double decomposition of ferric sulfate with barium acetate. ... 

Cellobiose was prepared first by Skraup and Konig by the saponification of the octaacetate with alcoholic potassium hydroxide, and the method was improved by Pringsheim and Merkatz.3 Aqueous barium hydroxide also has been employed for the purpose, and methyl alcoholic ammonia has been used extensively for the hydrolysis of carbohydrate acetates. The method of catalytic hydrolysis with a small quantity of sodium methylate was introduced by Zemplen,i who considered the action to be due to the addition of the reagent to the ester-carbonyl groups of the sugar acetate and the decomposition of the addition compound by reaction with alcohol. The present procedure, reported by Zemplen, Gerecs, and Hadacsy, is a considerable improvement over the original method (see Note 2). 

Barium carbonate decomposes to barium oxide and carbon dioxide when heated at 1,300°C. In the presence of carbon, decomposition occurs at lower temperatures. Barium carbonate dissolves in dilute HCl and HNO3 liberating CO2. Similar reaction occurs in acetic acid. The solid salts, chloride, nitrate and acetate that are water soluble may be obtained by evaporation of the solution. Dissolution in HF, followed by evaporation to dryness, and then heating to red heat, yields barium fluoride. 

Barium perferrate is the most stable salt of the series. It is insoluble in water, and its suspension in water may be boiled without decomposition. It is practically unaffected by dilute sulphuric acid in the cold. Apart from this it is readily attacked by acids, even carbonic dilute hydrochloric or nitric acid decomposes it instantly, yielding salts of barium and iron.5 When treated m the cold with very dilute hydrochloric acid, chlorine is evolved and the solution assumes a red colour, probably due to the presence of the Fe04" ion.G Acetic acid reacts similarly. On boiling, the solution evolves oxygen, and becomes colourless. 

The anhydrides can be prepared by the action of acetic anhydride on the corresponding malonic acid in the presence of a small amount of sulfuric acid, followed by neutralization of the mineral acid with powdered barium carbonate and evaporation to dryness in a high vacuum. The residual malonic anhydride is then heated to the decomposition point at a low pressure, and the ketene is collected in a cold receiver. This procedure has been applied to the synthesis of low-molecular-weight dialkylketenes (R is methyl, ethyl, f2-propyl, or isopropyl) in 50-80% yields. ... 

Phenylarsinophenyl-o-arsinic acid.—This compound (I) may be obtained in two ways (1) Diazotiscd o-arsanilic acid is coupled with phenylarsenoxide (from the dichloricle and 5N sodium hydroxide). The acid crystallises from hot dilute alkaline solution on treatment with hydrochloric acid in microscopic, long, quadrilateral plates, which melt with decomposition at 850° or 860° C. on rapid heating. It is sparingly soluble in acetic acid and very difficultly soluble in water and the usual organic solvents. From its ammoniacal solution barium hydroxide precipitates the barium salt as a white, insoluble jiowder. The copper salt is insoluble in water and dilute acetic acid. Azobenzenc-o-o -diarsinie acid,... 

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