EMULSIONS 



An emulsion contains two immiscible 

 liquids and a third colloidal substance mis- 

 cible to a greater or less degree with each of 

 the other two substances. 



I. KEROSENE EMULSION 



Procedure. — Weigh 5 grams of ordinary- 

 yellow soap cut into pieces to aid solution and 

 dissolv by the aid of heat in 40 cc. of water in 

 beaker. When solution is complete add 80 

 cc. of kerosene and stir vigorously, or pour 

 from one beaker to another, until the emul- 

 sion is complete as evinst by the disap- 

 pearance of the oil. This is a stock solution 

 wh'-ch is diluted with 2-10 parts of water as 

 required. 



Notebook. 



1. Dilute some of the emulsion and examin a drop 

 under the microscope. What is seen? 



2. What substance mixes, to a slight extent, with 

 both the kerosene and the water? 



3. Would the decomposition of this substance 

 destroy the emulsion? Verify by experiment and tell 

 how it was done. 



4. How long, upon standing, before kerosene sepa- 

 rates? 



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