PROPYL ALCOHOLS. 65 



tetrethyl. A liquid of pungent odor, congealing at 

 0, boiling at 208-210. 



Siliciumethyl, (C 2 H 5 ) 4 Si, is formed by heating 

 silicium chloride with zincethyl to 160. Colorless 

 liquid, boiling at 153, lighter than water and insolu- 

 ble in it. Yields with chlorine a liquid C 8 H 19 ClSi, 

 boiling at 180-190. 



3. Propyl Alcohols. 

 C 3 H 8 = C 3 H 7 .OH. 



Of the alcohols, which have the formula C 3 H 8 0, 

 there are two isomeric modifications possible, as was 

 shown at p. 32. Both are known. 



1. Normal propyl alcohol, CIP.CH 2 .CH 2 .OH. Is 



formed in the preparation of ethyl alcohol by fer- 

 mentation, together with some of the other alcohols of 

 this series, and is contained in the secondary products, 

 which boil at a higher temperature (fusel-oil). It can 

 be isolated from these by means of partial distillation, 

 but only with difficulty can it thus be obtained in a 

 pure condition. To prepare the pure alcohol, that 

 portion of fusel-oil that boils between 85-110 is 

 treated with amorphous phosphorus and bromine (see 

 ethyl bromide, p. 46), and thus converted into bro- 

 mides. These are then separated by partial distilla- 

 tion, the portion that boils at 71 decomposed with 

 silver acetate or potassium acetate, and the ether thus 

 formed decomposed by means of caustic potassa. It 

 is also produced by the action of hydrogen in statu 

 nascendi on propionic aldehyde, by the action of 

 sodium-amalgam on propionic anhydride, and together 

 with ethyl alcohol and other bodies by heating allyl 

 alcohol with caustic potassa. 



Colorless liquid, of a pleasant odor, of specific 

 gravity 0.8205 at ; boiling point, 97 ; mixes with 

 water, but not with a concentrated solution of calcium 

 chloride. Under the influence of oxydizing agents it 

 yields propionic aldehyde and propionic acid. 



6* 



