186 BBSBARCHES UPON THE CHEMICAL PROPERTIES OF GASES. 



Gold chloride No change cold; until after prolonged contact or on 



heating to lOOo. 



Silver nitrate Unchanged. 



Silver nitrate in amraoniacal solution Unchanged. 



Iridium chloride Unchanged, cold or at 100-^. 



Ruthenium chloride Unchanged. 



Rhodium chloride Unchanged. 



Potassium rutheniate Traces of reduction after twenty-four hours. 



Cerium dioxide in dilute sulphuric acid No change, cold or at 100°. 



Potassium permanganate , Slowly turns brown. 



Potassium permanganate acidulated with dilute sul- Quickly bleached. 



phuric acid. 



Potassium permanganate crystals in concentrated sul- Prompt oxidation to carbon dioxide. 



phuric acid. 



Chromic acid Unchanged. 



Osmic acid Quickly reduced, with precipitation of metal as a black 



powder. 



Ferric chloride Unchanged, cold or at tOOo. 



Bromine water Incomplete absorption, even after prolonged contact. 



Peroxide of hydrogen No carbon dioxide formed. 



Ferricyanide of potassium Unchanged. Not reduced to ferrocyauide. 



Calcium hypobromite containing excess of lime water. . Unchanged. 



Propylene is not absorbed by sulphuric acid in the cold. 



2. Reactions at High Temperatures. 



As regards reducing action upon metallic oxides, no important properties dis- 

 tinguishing propylene from ethylene can be named. 



Propylene conducted over crystals of iodic acid contained in a glass tube heated 

 in the oven undergoes oxidation, yielding iodine vapors and carbon dioxide at a tem- 

 perature approximating that of dissociation of the iodic acid. 



Comments. — Towards reagents in solution, propylene appears in some cases to 

 possess slightly greater stability than ethylene. This is especially the case with 

 gold chloride and potassium rutheniate. Like ethylene, it is not oxidized to carbon 

 dioxide by any of the reagents used in solution, with the exception of potassium 

 permanganate in concentrated sulphuric acid. Experiments with bromine water 

 have led to the same results as in the case of ethylene. The absorption is decidedly 

 incomplete. 



ISOBUTYLENE. 



This gas was prepared from isobutyl iodide by the method described on p. 167. 

 The reactions were in the majority of cases perfectly similar to those of ethylene 

 and propylene. 



