CYANOGEN COMPOUNDS. 217 



and methyl sulphate. Prismatic crystals, fusing at 

 175, and boiling at 295. Boiled with caustic potassa, 

 it yields methylamine and carbonic anhydride. 



Ethyl cyanurate, C 3 ^ 3 3 (C 2 H 3 ) 3 , is prepared like 

 the methyl ether. Colorless, rhombic crystals, which 

 fuse at 85 and boil at 276. Soluble in boiling water, 

 alcohol and ether. When boiled with caustic potassa, 

 it conducts itself like the methyl ether. 



Diethylcy anuric acid, C 3 ^ T3 3 (C 2 H 5 ) 2 H, can be best 

 obtained from the alcoholic mother-liquor from the 

 crystallization of crude ethyl cyanurate. This is boiled 

 with baryta water, the barium oxide removed by means 

 of sulphuric acid, and the filtrate evaporated. Rhom- 

 bohedral crystals, soluble in hot water, alcohol and 

 ether. Fuses at 173, volatile at a higher temperature. 

 Weak acid ; dissolves easily in alkalies ; on being eva 

 porated, however, these solutions yield the acid in the 

 free state. 



Cyanamides. 



Cyanamide, CEEp = CKOTI 2 , is formed by mix 

 ing gaseous or liquid cyanogen chloride with dry 

 ammonia gas ; and by the action of carbonic anhydride 

 on sodiurnamide. Is most easily obtained by conduct 

 ing cyanogen chloride into an anhydrous ethereal solu 

 tion of ammonia, filtering from the sal-ammoniac, 

 which is thrown down, and evaporating. Colorless 

 crystals, easily soluble in water, alcohol, and ether ; 

 fuses at 40. Its solution gives a yellow precipitate, 

 CN 2 Ag 2 , with silver nitrate and a little ammonia ; 

 when nitric acid is added to its solution, water is taken 

 up, and it is converted into urea. 



Dicyano-diamide, C 2 H 4 K 4 = (CNJTPN*. When 

 cyanamide is left to itself for some time, it is sponta 

 neously converted into dicyano-diamide ; or when its 

 aqueous solution is evaporated, the same change takes 

 place, especially when a little ammonia is previously 

 19 . 



