302 Mixter — Products of the Explosion of Acetylene. 



quantities of hydrocyanic acid and ammonia formed. The 

 potassium hydroxide solution through which the gaseous 

 products of the explosion were passed required 5 CC of a deci- 

 normal solution of silver nitrate to form a permanent precipi- 

 tate of silver cyanide, 5 CC more of the silver solution were added 

 in order to remove the cyanides from the solution, and the 

 precipitated silver cyanide was filtered off. The filtrate was 

 then cautiously distilled into hydrochloric acid. The acid solu- 

 tion was finally evaporated to dryness. The residue was 

 0*0035 gram of ammonium chloride, equivalent to 0*001 gram 

 of ammonia. As 5 CC of the silver solution correspond to 0*027 

 gram of hydrocyanic acid, the ratio between the ammonia and 

 hydrocyanic acid formed is apparent. 



In order to determine whether or not the gas after the explo- 

 sion contained cyanogen, the alkaline solution from which 

 ammonia was distilled was acidified with hydrochloric acid, 

 boiled, then made alkaline with potassium hydroxide. This 

 last solution gave when distilled no ammonia. If cyanogen 

 had been present in the gas, there would have been formed in 

 the solution of potassium hydroxide through which the gaseous 

 products of the explosion were passed, cyanide and cyanate. 

 The latter salt, as is well known, yields an ammonium salt 

 when treated with an acid. 



Experiment Ifi. — The mixture of acetylene and nitrogen 

 containing 28 per cent of the latter gas was allowed to stand 

 24 hours over a solution of ferrous sulphate mixed with 

 ferrous hydroxide in order to free the gas from oxygen and 

 possible traces of ammonia. The pressure of the gas before 

 the explosion was 3781 mm , a little less than 5 atmospheres, at 

 6*4°. The gas drawn from the bomb after the explosion when 

 the pressure was nearly 5 atmospheres contained 3*2 per cent 

 of acetylene, and that portion drawn at 1*3 atmospheres con- 

 tained 5*6. The hydrocyanic acid estimated as in previous 

 experiments was found to be '170 gram and 140 ec per liter in 

 the bomb. The ammonia found in the same volume of gase- 

 ous products was *0047 gram. Here we have a ratio of 1 of 

 ammonia to 36 of hydrocyanic acicl in the products of the 

 explosion. 



Experiment Jf-6. — The mixture of acetylene and nitrogen 

 containing 10 per cent of the latter was purified as in the 

 previous experiment. It was sparked when at a pressure of 

 3856 mm . The first portion of the gas drawn from the bomb 

 was found to contain 1*7 per cent of acetylene and that taken 

 at a pressure of 2 atmospheres 2*2 per cent. The hydrocyanic 

 acid found corresponded to 0*145 gram and 120 cc per liter in 

 the bomb. Likewise the ammonia was 0*0046 gram. Here 

 the ratio of the ammonia to the hydrocyanic acid is 1 to 30. 



