PRACTICAL ORGANIC AND BIO-CHEMISTRY 



another. 



II. SEPARATION OF LIQUIDS. 

 A. Mechanically. 



(a) Two liquids, if they are not miscible, are easily separated from one 

 They are placed in a tap funnel or separating funnel (Fig. 3), 

 either cylindrical or pear-shaped according to the 

 volume, the stopper is removed and the heavier 

 liquid run out and collected. The (lighter liquid is 

 poured out through the top so as to avoid contamina- 

 tion by coming in contact with drops of the other 

 liquid remainingiin the stem. 



(b) Two liquids, if they are miscible, may not both 

 be soluble in the same solvent ; such a solvent must 

 not be miscible with one of the constituents. On 

 shaking the mixture with the solvent in a separating 

 funnel, the mixture will separate into two layers. In 

 shaking up two liquids in a separating funnel, the 

 stopper of the funnel is held in the palm of one hand, 

 and as usually an increase of pressure occurs, especi- 

 ally if ether and water be the liquids, the tap of the 



Fio. j. 



funnel is occasionally opened after allowing the liquids to settle at the 

 other end. After thoroughly shaking, the liquids are allowed to separate, 

 the stopper is removed and the heavier liquid is run out. The insoluble 

 liquid is shaken up once or twice more with more solvent, and is puri- 

 fied by drying, if necessary, and distillation. The solvent, if water be 

 one of the liquids, is dried by shaking it, or allowing it to stand for 

 12-24 hours with solid calcium chloride, or sodium sulphate, or potas- 

 sium carbonate. It is separated from the soluble constituent by frac- 

 tional distillation, or treated as the case necessitates. 



As an example, a mixture of equal parts of alcohol (50 c.c.) and 

 chloroform may be made. On shaking up with two volumes of water 

 in a separating funnel, the chloroform separates and sinks. It is re- 

 moved and the other constituents are poured out. The chloroform is 

 returned and shaken once more with water. It is run out and the 

 moisture is removed by shaking or standing with some calcium chloride 

 from which it is filtered and then distilled. 



