RESEAKCHES UPON THE CHERIICAL PROPERTIES OF GASES. 



189 



permanganate or gold chloride. By these three reagents it is best distinguished from 

 the true olefines. 



It may be mentioned that ether vapor, which so frequently contaminates the 

 olefines, does not reduce palladium chloride solution. 



CARBONIC OXIDE. 



This gas was prepared by heating a mixture of pure oxalic acid and sulphuric 

 acid and purified by caustic soda solution. 



1. Reactions in Solution. 



REAGENTS. 



Palladium chloride 



Platinum chloride. 



Gold chloride 



Gold chloride in excess of potassium hydroxide. 



Silver nitrate 



Ammoniacal silver nitrate 



Iridium chloride. . , 

 Rhodium chloride. 



Potassium rutheniate . 



Cerium dioxide in dilute sulphuric acid. 

 Potassium permanganate 



Chromic acid. 



Osmic acid 



Ferric chloride . 



Hydrogen peroxide 



A. P. S. — VOL. XVII. Y 



REACTIONS. 



Quickly reduced, with oxidation of carbon monoxide to 

 carbon dioxide. The reaction is very delicate in 

 strongly acid solutions or in solutions of the pure, 

 dry chloride in water. 



Carhon monoxide is oxidized to carbon dioxide, cold or 

 at lOQo. A reduction of the platinum salt to a 

 lower chloride occurs, the solution assuming a 

 darker color. After prolonged contact (several days 

 or even weeks) an incomplete precipitation some- 

 times, but not always, occurs. 



Quickly reduced to metallic gold in form of a brown 

 powder, the carbon monoxide being rapidly oxi- 

 dized lo carbon dioxide, cold or at 100°. 



Immediately reduced. Very delicate reaction (of the 

 first class). 



Unchanged. 



Slow reduction to metallic silver, which separates as a 

 black powder. The filtrate from the precipitated 

 silver was found to contain nitrous acid (as a result 

 of the action of the carbon monoxide on silver ni- 

 trate in ammonia) when tested by Griess' reaction - 



Slowly reduced to metal. 



Unchanged cold ; slowly reduced at lOO'^ (reaction of 

 the third class). 



Rapidly reduced. Metallic ruthenium separates as a 

 black powder. 



Unchanged, cold or at 100°. 



Quickly reduced, whether in neutral, alkaline or acid 

 solution. 



No change of color occurs, but a trace of carbon diox- 

 ide is formed (reaction of the third class). 



Quickly reduced. 



Ferrous chloride is produced in traces after prolonged 

 contact. 



No oxidation to carbon dioxide. 



