Dr. Playfair on Palmic Acid. 4/7 



The silver salt burned with oxide of copper gave the follow- 

 ing results : — 



I. 0*395 grm. gave 0*751 carbonic acid, and 0*303 water. 



II. 0*2590 grm. gave 0*5005 carbonic acid, and 0*192 

 water. 



III. 0*2990 grm. gave 0*5770 carbonic acid, and 0*2190 



water. 



I. II. HI. 



Carbon. . . . 51*64 52*66 52*64 



Hydrogen . . 8*52 8*23 8*12 



Oxygen . . . 12*48 11*75 11*88 



Silver .... 27*36 27'36 27*36 



From these data the following theoretical composition is 



calculated : — 



In 100 Parts. 



34 Carbon .... 2550 52*05 



32 Hydrogen . . 400 8*16 



6 Oxygen ... 600 12*26 



1 Silver .... 1349 27'53 



4899 



Hence the theoretical composition of the anhydrous acid 

 is, 



This agrees closely with the numbers found in the analysis 

 of the acid, showing that it is anhydrous, and possesses the 

 formula C^ H 32 O s . 



I remarked that the acid obtained by saponifying palmine 

 had a melting-point which never exceeded 112°, while the 

 acid prepared directly by crystallizing the solidified fatty acids 

 without saponification possessed a melting-point 2° higher. 

 To ascertain whether any change took place upon saponifica- 

 tion, a portion of pure palmic acid, procured as formerly de- 

 scribed, was saponified by potash, liberated by hydrochloric 

 acid, crystallized out of alcohol and analysed. Its melting- 

 point was 111°*5 F. 



I. 0*1575 grm. acid gave 0*414 carbonic acid, and 0*1635 

 water. 



II. 0*166 grm. substance gave 0*4345 carbonic acid, and 

 0*171 water. 



III. 0*0805 grm. substance gave 0*2115 carbonic acid, and 

 0*0835 water. 



