108 MASS. EXPERIMENT STATION BULLETIN 166. 



Laurie is classed as "insoluble," although slightly soluble in boiling 

 water. 



A soluble dibasic acid occurs in Japan wax which is not volatile. 



Neutralization Number. — The neutralization number indicates the 

 number of milligrams of potassium hydroxide required to neutralize 1 

 gram of soluble fatty acids. 



The difference between the saponification number (s) of the fat and the 

 product of the percentage of insoluble fatty acids (I) times their neutral- 

 ization number (ui) indicates the milligrams of potassium hydroxide re- 

 quired to neutralize the soluble fatty acids in 1 gram of fat, wliich, di- 

 vided by the percentage of soluble fatty acids (S), gives the neutralization 

 number (n) of the soluble fatty acids. 



S 



Mean Molecular Weight. — The molecular weight (m) of the soluble 

 fatty acids can be calculated from the neutralization number (n) by 

 means of the formula — 



„ 56108 



Neutralization Numbers of Soluble Fatty Acids. 



Acid. 



Formula. 



Molecular 

 Weight. 



Neutraliza- 

 tion 

 Number. 



Acetic, . 

 Butyric, . 

 Valeric, . 

 Caproic, . 

 Caprylic, 

 Capric, . 



CHsCOOH 



C3H7COOH 

 C4H9COOH 

 CsHuCOOH 

 C7H16COOH 

 C9H19COOH 



CO. 032 

 88.064 

 102.080 

 110. 09G 

 144.128 

 172.160 



934.635 

 637.128 

 549.647 

 483.290 

 389.293 

 325.906 



Glycerides of Soluble Fatty Acids. — The percentage of triglycerides (Sg) 

 can be calculated from the percentage (S) and molecular weight (m) of 

 the soluble fatty acids by the formula — 



grr = 3 m +38.016 ^ g 

 3 m 



Glycerol in the Glycerides of Soluble Acids. — The percentage of glycerol 

 (G) in the glycerides of soluble acids can be calculated from the per- 

 centage (S) and molecular weight (m) of the soluble acids : — 



G = 



9 2 .064 

 3 m 



XS 



