Barium arsonoacetate

The filtrate is poured into a solution containing 185 g. of crystallized barium chloride dissolved in 600 cc. of hot water. Barium arsonoacetate, Ba(02CCH2As03Ba)2 (hydrated), forms a thick, finely divided precipitate. The mixture is stirred for several minutes and then allowed to stand until the following day, when it is filtered upon a 15-cm. Buchner funnel and washed... 

Sodium arsonoacetate is prepared by adding the freshly filtered and washed barium arsonoacetate as obtained above (without drying) to a solution of 108 g. of anhydrous sodium sulfate in 500 cc. of hot water. The mixture is mechanically stirred for one hour, the barium sulfate filtered off, and the filtrate concentrated on the steam bath until crystallisation commences. Upon cooling and stirring (Note 3), sodium arsonoacetate separates and is filtered by suction, the filtrate being concentrated to obtain a second crop of crystals. The yield of the combined fractions is 100-110 g. (80-88 per cent of the theoretical amount). 

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