3S Dr. Stenhouse on the Action of Bromine 



of bromine. It is clear from the results of the above analyses, 

 therefore, that the bromopicrine prepared in the manner just de- 

 scribed is impure, and contains a quantity of a substance which is 

 richer in bromine, most probably the carburet of bromine (C^Br*), 

 which maybe readilyproduced by the long- continued actionof bro- 

 mine on bromopicrine. It is necessary, therefore, to prepare 

 bromopicrine by some other process where such a decomposition 

 is not likely to be produced. Nitropicric acid was consequently 

 digested with excess of hypobromite of lime, in a manner pre- 

 cisely similar to that by which I many years ago prepared 

 chloropicrine. The bromopicrine obtained was washed with 

 solution of carbonate of soda, agitated with mercury, and ren- 

 dered anhydrous by chloride of calcium. When analysed — , 



I. 0-6645 grm., when ignited with quick lime, gave 1*2495 

 grm. of bromide of silver. 



II. 0*5225 grm., when ignited with quick lime, gave 0*9825 

 grm. of bromide of silver. 



Theory. Found. 



^ * , <—• ■■ ' ^ 



I. II. 



C? = 12 403 



Br* =240 80-54 80*01 8002 



N0*= 46 15-43 



298 10000 



Bromopicrine is a colourless liquid, which is heavier than 

 water; its jodour very closely resembles that of chloropicrine, 

 and its vapour attacks the eyes very strongly. It is very slightly 

 soluble in water^ but readily dissolves in alcohol and aether. Its 

 alcoholic solution is not immediately precipitated by nitrate of 

 silver ; but on standing for some time, even in the cold, and im- 

 mediately on the application of heat, bromide of silver precipitates. 

 When bromopicrine is strongly heated, it is decomposed with a 

 slight explosion. Bromopicrine is therefore a much less stable 

 compound than chloropicrine, which in most other respects it 

 80 closely resembles. 



Broinanil, C^^Br'^0'*. — The residual matters remaining in the 

 retort after the distillation of the bromopicrine produced by the 

 digestion of bromine with nitropicric acid, were found to consist 

 chiefly of bromanil and some un decomposed nitropicric acid. 

 The excess of nitropicric acid was removed by repeated digestion 

 with hot water, when a quantity of impure bromanil remained as 

 yellowish-red crystalline scales. These scales contained a small 

 quantity of a reddish resinous substance, which was readily 

 removed from the bromanil by taking advantage of its greater 

 solubility in alcohol and aether. When the bromanil had been 

 twice crystallized out of alcohol, it formed beautiful crystalr 



