3fixter — Products of the Explosion of Acetylene. 307 













C. C. at 









Per cent 



C. C. at 0° 



and 760 mn 









of C 2 H 2 in 



and 760 mm 



of HON 



So. of 





Pressure 



gas after 



of C 2 H 2 per 



per 1. in 



Exp. 





in atmospheres. 



explosion. 



1. in bomb. 



bomb. 



29 





3 



4 



120 





30 





3 



4-1 



123 





36 





2 



4- 



80 





39 





1-95 



3-3 



66 





40 





5-1 



2-4 



122 





41 





3'2 N 10-7 # 



1-4 



45 



63 



42 





4' N15 " 



0-25 



10 



140 



43 





5- N23 " 



2-1 



105 



165 



45 





5- N 28 " 



4-4 



220 



140 



46 





5' 10 



2- 



100 



120 



51 in 



U-tube 



2-7 



3- 



81 





52 



u 



3- 



1-7 



51 





53 



a 



2'5 N 15 " 



1-3 



32 







54 " 2-5 13 " Not estimated. 



The above are all of the results obtained with the bomb, fig. 

 1, and with the iron U-tube having the same diameter as the 

 bomb, excepting experiments 31 to 35 described in the first 

 paper. The amounts of acetylene and hydrocyanic acid found 

 in the residual gas drawn from the bomb do not include quite 

 all of these compounds, as there was some condensation on the 

 carbon. This is evident from the fact that gas taken at 4 or 

 5 atmospheres contained less acetylene than that taken at lower 

 pressures. The above data derived from the experiments are 

 not sufficient to yield the relation between the pressure and 

 the quantity of acetylene in the residual products. It is obvi- 

 ous, however, that at the lowest pressure at which explosion 

 will occur the total quantity of acetylene left in the bomb is 

 much less than when the initial pressure is 3 or more atmos- 

 pheres. The small amounts found in experiments 51, 52 and 

 53 show that a more rapid cooling in the large iron U-tube than 

 occurs in the bomb does not increase the acetylene in the 

 residual gas. This fact supports the view expressed in the first 

 paper that the acetylene in the gas after explosion is not an 

 undecomposed portion of the original gas. 



There is, however, no question about the synthesis of hydro- 

 cyanic acid in the explosions of mixtures of acetylene and 

 nitrogen in the bomb. But in the U-tube the nitrogen did not 

 combine. In the former instances the molecules of nitrogen 

 either acquired energy adequate for combination or were dis- 

 sociated, while in the latter they remained in the inert condi- 

 tion characteristic of the element. The velocity of explosion 



