ETHYLENE SERIES. 113 



1. Ethylene (Elayl, Olefiant Gas). 

 C 2 H 4 =CH 2 :CH 2 . 



Formation and preparation. By the destructive dis 

 tillation of the salts of a great many fatty acids ; by 

 distillation of fats, resins, wood, of anthracite coal, 

 and a large number of other organic bodies. Prepared 

 most easily by heating a mixture of 1 part alcohol and 

 4 parts concentrated sulphuric acid, to which has been 

 added sand enough to form a thick pulp, in order to 

 prevent foaming. The gas, which is cooled, is con 

 ducted through soda ley and sulphuric acid, in order 

 to free it of carbonic and sulphurous anhydrides, alco 

 hol and ether vapors. 



Properties. Colorless gas ; specific gravity, 0.978 ; 

 not congealing above 110 ; burns with a luminous 

 flame, and is absorbed but little by water. When con 

 ducted through an ignited tube, it is decomposed into 

 carbon, marsh gas, hydrogen, and acetylene. It com 

 bines with sulphuric anhydride to form carbyl sul 

 phate ; English sulphuric acid absorbs it very slowly, 

 forming ethylsulphuric acid. Hydrochloric, hydro- 

 bromic, and hydriodic acids combine slowly with it, 

 forming ethyl chloride, bromide, and iodide. A solu 

 tion of platinum chloride in hydrochloric acid absorbs 

 it slowly and, on the addition of potassium chloride, 

 lemon-colored crystals of C 2 H 4 .PtCl 2 .KCl + H 2 are 

 deposited. 



Ethylene chloride (Elayl chloride), C 2 H 4 C1 2 = 

 CII 2 C1.CH 2 C1, is formed from ethylene and chlorine by 

 direct combination. In order to prepare it, ethylene 

 gas is conducted into a gently heated chlorine mixture 

 and the chloride finally &quot;distilled off. Colorless liquid, 

 of an ethereal odor ; of specific gravity 1.271 at ; 

 boiling point, 85. When boiled with alcoholic po- 

 tassa, it is converted into chlor ethylene, C 2 IPC1, water 

 and potassium chloride being formed at the same time. 

 A gas condensable at --18. Chlorine acts upon 

 ethylene chloride, yielding substitution-products, and, 

 according to the length of time occupied in the action, 



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