ETHYLBENZENE. 285 



3. Paraxylene. Prepared, like toluene, by the de 

 composition of a mixture of parabrom toluene or para- 

 dibrombenzene, and methyl iodide with metallic 

 sodium. Colorless liquid, boiling at 136. At a low 

 temperature, solid and crystalline. Fusing point, 15. 

 Dilute nitric acid oxidizes it to paratoluic acid ; chro 

 mic acid to terephtalic acid. 



Dibromparaxylene, C 6 H 2 Br 2 (CH 3 ) 2 , resembles di- 

 brommetaxylene in all its properties, and melts like 

 this at 12. Tollylenebromide, C 6 H 4 (CH 2 Br) 2 , is formed 

 by the action of bromine on boiling paraxylene. Color 

 less, lamellar crystals ; fusing point, 145-147. 



Dinitroparaxylene, C 8 H 8 (N0 2 ) 2 . Is formed by the 

 action of fuming nitric acid on paraxylene. Two iso- 

 meric modifications are produced at the same time, of 

 which the one forms long, thin needles, more difficultly 

 soluble in alcohol, fusing at 123.5; the other large, 

 monoclinate crystals, more easily soluble in alcohol, 

 fusing at $Z . Trinitroparaxylene, C 8 H 7 (N0 2 ) 3 . Long, 

 colorless needles. Fusing point, 137. Moderately 

 easily soluble in hot alcohol, but sparingly in cold. 



b. Ethylbenzene. 

 C 6 H 5 .CH 2 .CH 3 . 



Is obtained by the action of sodium on a mixture of 

 brombenzene and ethyl bromide, which is diluted 

 with ether. Colorless liquid, boiling at 134 ; specific 

 gravity, 0.866. Oxidized either with dilute nitric acid 

 or chromic acid, it yields benzoic acid. 



Bromethylbenzene, C 6 H 4 Br.C 2 H 5 . Colorless liquid, 

 boiling at 199. Benzene-ethyl bromide, C 6 IRCH 2 . 

 CH 2 Br, and chloride, C 6 IP.CH 2 .CH 2 C1, are produced by 

 the action of bromine or chlorine on ethylbenzene with 

 the aid of heat. Liquids that cannot be distilled with 

 out undergoing decomposition. The chloride is con 

 verted into benzene-ethyl cyanide, C 6 H 5 .CH 2 .CH 2 .GI$r, by 

 boiling with potassium cyanide and alcohol. 



