2. MONOSACCHARIDS (grape sugar, etc). 



a. Dextrose. Make a one per cent solution in hot water. Test 

 solution as follows : 



(i). Add iodine. Result? Is starch present? 



(2). Add }/4 its volume of strong potassium hydroxide and heat 

 gradually to boiling point. Xote color and odor (Moore's test). 



(3). Add a few drops of copper sulphate solution, then ]/> its 

 volume of 10 per cent caustic potash and boil. Result? (Trommer's 

 test). 



(4). Boil a little Fehling's solutions in a test tube. Result? Then 

 add some sugar solution and boil again. Result? 



3. FERMENT ACTION : ENZYMES. 



a. Salivary diastase ; Ptyalin. Collect a few cc. of saliva in a 

 test tube ; dilute with about five volumes of water and filter. Make 

 the following mixtures : 



1. Equal volumes dilute starch paste and saliva solution. 



2. The same using saliva that has been previously boiled. Place 

 tubes in incubator warmed to 40 C. After fifteen minutes, test each 

 mixture for starch (iodine) and sugar (Fehling's). What effect 

 does ptyalin have on starch ? What effect does boiling have on 

 ptyalin ? 



II. HYDROCARBONS (Oils, Fats). 



(i) Xote physical properties, differences in melting point, etc., 

 of three fats, olive oil, butter and tallow. Test solubilities of these 

 fats in water, alcohol, chloroform, ether. (2) Shake a few 

 drops of olive oil with water in a test tube. What happens? Set 

 tube aside for a few minutes. What happens? Shake up a few 

 drops of the oil with one per cent sodium carbonate instead of water, 

 examine with microscope, and note difference in results. (This is 

 an emulsion. ) (3) Place a small amount of butter on a slide, and 

 put on it a drop of 2 per cent osmic acid. Observe under microscope 

 what occurs. 



2. CHEMICAL TESTS FOR FATS. The reaction with ether and 

 osmic acid are two well known tests for fats. 



III. PROTEIDS (Albumens, etc.). 



Use white of egg as type of proteid. 



i. Carefully pour white of egg into a dish. This is approxi- 

 mately a 12 per cent solution of a proteid (albumen). Notice its 

 consistency; observe that it can be drawn out into threads. Test 

 its reaction with litmus paper ; is it acid, alkaline, or neutral ? Of 



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