50 P. T. Austen—Dinitroparadibrombenzol 
It is not a little peculiar that nitric acid should drive the bro- 
mine atom out of dinitrobromphenol, forming picric acid; for 
picric acid when treated with bromine, yields* dinitrobrom- 
phenol. 
Solubility.—Difficultly soluble in boiling water. Apparently 
less easily soluble in boiling dilute hydrochloric and nitric acids. 
Easily soluble in boiling dilute sulphuric acid. In hot alcohol 
and acetic acid (glacial) very easily soluble. In carbon disul- 
phide, less easily. In hot aniline it is very easily dissolved, 
giving a red solution. 
Silver Beta-dinitroparabromphenylate. 
Preparation.—The salt was made by mixing aqueous solutions 
of silver nitrate and ammonium dinitrobromphenylate. It is dif- 
ficultly soluble in boiling water, but much more easily in alcohol. 
NO, 
cu. N°.=0,H,N ,0,AgBr. 
(OAg 
0°4903 grams of substance yielded 0°1884 grams of AgCl. 
Cal 
culated. 
Ag=29°19 28°90 
hse cong ag glittering red needles, having a brilliant 
green reflex. hen dry the salt puffs on heating, If thrown 
on a hot surface, it explodes. 
Potassium Beta-dinitroparabromphenylate. 
J have already described the formation of this salt. It is 
somewhat difficultly soluble in boiling water. It forms long 
glittering and red needles, having a greenish reflex. This 
is the only salt that Korner prepared. He considers the play 
of colors to be like that of murexide. 
Barium Beta-dinitroparabromphenylate. 
Preparation.—Barium carbonate was boiled with a dilute 
alcoholic solution of the phenol until all carbonic anhydride 
was expell The residue was extracted with boiling water, 
filtered and allowed to crystallize. 
nalysis.— 
(C,H,(NO,),BrO) ,Ba=C,,H,K,O, Br, Ba 
0°3824 grams of substance gave 0°1331 grams of BaSO,. 
Calculated. Found. 
Ba=20°72 20°46 
Properties.—Saffron-yellow needles. Moderately soluble in 
hot water or alcohol. When heated in a mattrass, it explodes, 
covering the sides with carbon. 
* Armstrong, Ber. d. d. Chem. Ges., vi, 650. 
