138 GLYCOLS. 



pitates the hydroxides from solutions of metallic salts. 

 It unites with water, when heated with it to 100 in 

 sealed tubes, forming ethylene alcohol ; with the lat- 

 ter, forming diethylene alcohol C 4 H 10 3 =GH 2 .OH.CH 2 .O. 

 CH 2 .CH 2 .OH (a liquid, boiling at 250) and triethylene al- 

 cohol C 6 H 14 O 4 = CH 2 .OH.CH 2 .O.CH 2 .CH 2 .O.CH 2 .CH 2 .OH 

 (boiling point, 285-289). Is converted into ethyl 

 alcohol by nascent hydrogen (from sodium-amalgam 

 and water). 



Ethylene sulphydrate (Glycolmercaptan), C 2 H 4 

 (SH) 2 , is formed by the action of ethylene chloride or 

 bromide on an alcoholic solution of potassium sulph- 

 ydrate. Colorless oil, of a penetrating odor. It forms 

 salts with metallic oxides, like ethylmercaptan. 

 Ethylene chlorhydrine gives a similar compound 

 with potassium sulphydrate, ethylene monosulphydrate 



SH. 



Ethylene sulphide, By the action of ethylene 

 chloride or bromide on an alcoholic solution of potas- 

 sium sulphide, a crystalline substance, diethylene sul- 

 phide (C 2 H 4 ) 2 S 2 is formed, together with an amorphous 

 yellow powder C 2 H 4 S, which is prepared most readily 

 by double decomposition of mercurio-glycolmercaptan 

 C 2 H 4 .S 2 Hg with ethylene bromide at 150. Fuses at 

 111, and boils undecomposed at 200. It unites directly 

 with chlorine, bromine, iodine, with oxygen and several 

 salts. Amorphous ethylene sulphide is converted into 

 diethylene sulphide by being heated alone or with car- 

 bon bisulphide. 



Ethylene monacetate, C 2 H 4 j QJ^ 1130 Ethylene 



bromide (1 part) is heated on a water-bath for a length 

 of time with potassium acetate (1 part) and alcohol (2 

 parts) in a flask connected with an inverted condensing 

 apparatus. It is separated and purified by means of 

 distillation. A liquid, boiling at 182, mixes with 

 water and alcohol. Hydrochloric acic] gas decora- 



