TEST FOR OLEOMARGARINE 91 



concentrate amount of borax present. Add as much 

 alcohol as there is milk present, and ignite. A green 

 flame indicates the presence of borax. 



Test for Salicylic Acid. C 6 H 4 OHCOOH 



1. Place a few crystals of salicylic acid in \ pint 

 of milk and agitate thoroughly as in the previous 

 tests. Pour a small quantity of same in test bottle 

 and add about the same quantity of sulphuric acid, 

 with about 30 c.c. of chloroform or ether. These 

 dissolve the fat present and greatly facilitate the 

 test. Add a few drops of ferric chloride. The pres- 

 ence of salicylic acid is indicated by a purple or 

 violet color similar to that of formaldehyde. The 

 distinction between these tests being that the color 

 reaction does not appear in the presence of salicylic 

 acid unless ferric chloride (Fe 2 Cl e ) be used, but ap- 

 pears in the presence of formaldehyde in either case. 



2. Place 5 c.c. suspected solution in porcelain dish 

 and evaporate to dryness. Warm residue with one 

 drop of concentrated nitric acid. Add two or three 

 drops of ammonia until alkaline. The presence of 

 salicylic acid is indicated by the formation of a 

 yellow color or ammonium picrate which will dye a 

 thread of fat free wool. 



EXERCISE XXII 



TEST FOR OLEOMARGARINE 



Place 5 grams or any convenient amount of oleo- 

 margarine in a small dish and apply flame. Place in 



