330 BENZOIC ACID. 



point, 234-235), and Pentabrombenzoic acid, C 7 HBi^0 2 

 (fusing point, 234-235), are formed by heating benzoic 

 acid with bromine to 200 and over. 



Paraiodobenzoic acid, C 7 H 5 I0 2 . From paraiodo- 

 toluene by oxidation. Colorless scales ; fusing point, 

 250. 



Fluorbenzoic acid, C 7 H 5 F10 2 . Is produced by 

 treating diazoamidobenzoic acid with hydrofluoric 

 ac id. Rhombic prisms ; fusing point, 182. 



Orthonitrobenzoic acid, C 7 H 5 (N0 2 )0 2 . Is obtained 

 by oxidation of nitrocinnamic acid (which see). Easily 

 soluble in water, fuses at 232. Metanitrobenzoic add 

 is formed by treating benzoic acid with hot very con- 

 centrated nitric acid, or with a mixture of sulphuric 

 and nitric acids. Crystallizes in fine needles or laminse, 

 which fuse at 141-142. Paranitrobenzoic acid (Nitro- 

 dracylic acid) is produced by the oxidation of para- 

 nitrotoluene. Slightly yellowish colored laminae, that 

 fuse at 240. Much less easily soluble in water than 

 the two isomeric compounds. 



Dinitrobenzoic acid, C 7 H 4 (N0 2 ) 2 2 . By continued 

 heating of metanitrobenzoic acid with a mixture of 

 nitric and sulphuric acids. Crystallizes from water in 

 large, very thin quadratic plates; from alcohol in prisms. 

 Fusing point, 204-205. 



By treating chlor- or brombenzoic acids with nitric 

 acid, there are formed chlornitro- and bromnitrobenzoic 

 acids. From metabrombenzoic acid are formed simul- 

 taneously two isomeric modifications a-bromnitrobenzoic 

 acid (fusing point, 246-248, but very slightly soluble 

 in water), and p-bromnitrobenzoic acid (fusing point, 140 

 141, more easily soluble in water). 



Ortho*amidobenzoic acid (Anthranilic acid), 

 C 6 II 4 (NH 2 ).CO.OH. Is formed, when indigo (1 part) 

 is boiled with soda-ley (10 parts, of 1.38 specific 

 gravity) for several days, finely powdered black oxide 



