142 GLYCOLS, 



produced by the action of fuming sulphuric acid on 

 ethyl cyanide or propionamide; by the oxidation of 

 ethylene sulphydrate with nitric acid; the sodium salt 

 is formed by heating ethylene bromide with a concen- 

 trated solution of "sodium sulphite. Easily soluble 

 crystals; fusing point, 94. Bibasic, very stable acid. 



Carbyl sulphate (ethionic anhydride). C 2 H 4 S 2 6 = 

 CH 2 SO 2 



CTT 2 O SO 2 ^ ^' ' l8 f rme( ^ by ^ ne direct union of 

 ethylene with sulphuric anhydride. Colorless crystals, 

 fusing at 80; deliquesces in the air, and combines 

 with water, forming 



CH 2 .O.S0 2 .OH 



Ethionic acid, C2H6S2 7 = CH 2 SO 2 OH This 

 acid is formed particularly when sulphuric anhydride 

 is conducted into alcohol, which is cooled by means of 

 ice. Bibasic acid, which is resolved into isethionic 

 acid and sulphuric acid when its aqueous solution is 

 evaporated. Its salts are also decomposed by boiling 

 their aqueous solutions. 



2. Propylene Alcohol (Propylglycol). 

 C3H 8 2 = C 3 H 6 (OH) 2 . 



Taking for granted that alcohols, which contain 

 two hydroxyl groups in combination with the same 

 carbon atom, cannot exist, there are only two diatomic 

 alcohols C 3 H 8 2 possible, viz.: CH 2 (OH).CH 2 .CH 2 (OH) 

 and CH 2 (OH).CH(OH).CH 3 . The first is a primary 

 alcohol, the second half primary, half secondary. Only 

 the second alcohol is known as yet. 



Preparation. From propylene bromide in the same 

 manner as ethylene alcohol from ethylene bromide. 



Properties. Colorless, viscid liquid ; specific gravity, 

 1.051 at 0; boiling point, 188-189; mixes with 

 alcohol and water in all proportions. When heated 

 with concentrated hydriodic acid, it is converted into 

 isopropyl alcohol and isopropyl iodide. 



