220 ANNUAL OF SCIENTIFIC DISCOVEFwY. 



DIRECT OXIDATION OF HYDROCARBONS. 



Bertholot has made the extremely interesting discoveiy that 

 vari(nis hydrocarbons maybe oxidated iminediatidy, and without 

 loss of carbon, with the production of neutral bodies, such as 

 aldehydes and their congeners. He operated with crystallized 

 chromic acid, dissolved in a small quantity of water. Ture ethy- 

 lene (freed from vai)or of ether by repeated washin^^s with con- 

 centrated sulphuric acid) is attacked slowly at 120°'C. (2^8° F.) 

 with formation of aldchvde 



In the cold, or even at 100° C, after many hours, no apprecinble 

 reaction was' found. The aldehyde was separated by distillation 

 and crystallized aldehyde-ammoniti prepared from it. 



Pure propylene was oxidated much more readily and almost at 

 the ordintiry temperature, in a few hours a great quantity of 

 acetone being formed : — 



CoHe + O. = Co He Oo. 



This acetone is easily isolated by simple distillation. Some 

 acetic acid appears, being a secondary product from the acetone. 

 Amylene is attacked violently, at the ordinar}' temperature, with 

 formation of complex protluots, derived, however, doubtless as 

 secondary products of oxidation of an acetone, CioHioO^, which 

 may be obtained by moderating the reaction. Acetylene is oxi- 

 dated in the cold, with heat, and ^jroduction of formic and car- 

 bonic acids. 



C/rygtallized camphcne is changed easily into camphor by pure 

 CrOa, on heating gentlv : — 



C20H16 -1-02 = CaoHicOo ; 

 the reaction being easier than that with platinum-black, long since 

 discovered by Berthelot. 



The name camphene is given by Berthelot and some other French 

 chemists to the solid hydrocarbon, isomeric with oil of tur2)entine 

 itself, whivh is separated by alkalies from the crystalline compound 

 that turpentine forms with muriatic acid. 



In conclusion, he reniaiks that the oxidating action of pure 

 CrOa is not exactly equivalent to that of mixed bichromate of potas- 

 sium and sulphuric acid ; in the latter the pi'esence of the sulphu- 

 ric acid, as well as the heat evolved in the formation of the chro-mic 

 and potassic sulphates, modifying the action. — Amer. Gas Light 

 Journal. 



ACTION OF THE ELECTRIC SPARK ON MARSII GAS. 



The production of acetylene by this process was announced by 

 Berthelot eight years ago ; he now says all organic gases and vapors 

 (of course which contain both C and H) yield acetylene under 

 the same influence. Indeed, this is a characteristic and sensitive 

 reaction, permitting him to detect the presence in hydrogen gas 

 of compound vapors of feeble tensions at ordinary temperatures. 



