TOLUENE. 273 



moist silver oxide mercurymonophenyl hydroxide, C 6 H 5 . 

 Hg.OH, is produced. This crystallizes in small, white, 

 rhombic prisms, and is a stronger base than ammonia. 



Tin triethylphenyl, C 6 H 5 (C 2 H 5 ) 3 Sn. Is obtained 

 by treating a solution of monobrombenzene and tin- 

 triethyl iodide in ether with sodium. Colorless liquid, 

 of a not unpleasant odor ; boiling point, 254 ; easily 

 soluble in ether and absolute alcohol, difficultly in 

 dilute alcohol, insoluble in water. It possesses a strong 

 refracting power ; specific gravity at 0, 1.2639 ; burns 

 with a luminous flame, leaving a residue of metallic 

 tin. Is reduced by silver nitrate to diphenyl. Hydro- 

 chloric acid decomposes it, yielding tintriethyl chloride 

 and benzene. 



2. Toluene (Methylbenzene, Toluol). 

 C 7 H 8 = C 6 H 5 .CH 3 . 



Preparation. From light oil by partial distillation. 

 By distilling a mixture of toluic acid with an excess of 

 lime. By treating a mixture of monobrombenzene 

 and ethyl iodide with an excess of sodium, the mix- 

 ture being diluted with ether and kept well cooled. 



It is also produced by the dry distillation of tolu- 

 balsam and many resins. 



Properties. Colorless liquid of an odor resembling 

 that of benzene ; specific gravity, 0.88 ; boiling point, 

 111. Oxidized with dilute nitric acid or chromic 

 acid, it is converted into benzoic acid. 



Substitution-products of Toluene. According 

 as the subtituting chlorine, bromine, and iodine take 

 the place of hydrogen in the benzene residue, or in the 

 methyl, compounds of the same composition but of 

 entirely different properties are formed. Chlorine, etc., 

 that has entered the benzene residue, is held as tena- 

 ciously in combination as in chlorbenzene ; that which 

 has entered the methyl-group, on the other hand, can 

 be replaced by other monovalent elements or atomic 



