MONOBASIC FATTY ACIDS, 



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radical (of the same kind as the one forming the acid) the so-called 

 anhydrides are produced, which correspond to the inorganic anhy- 

 drides. For instance : 



Nitric acid. 



N0 2 \o 

 N0 2 / 



Nitric anhydride. 



C 2 H 4 O 2 or C 2 H 3 O.OH. 

 Acetic acid. 



C 2 H 3 0\ 

 C 2 H 3 0/ a 



Acetic andydride. 



It is evident from the above that, while acids are hydroxides of 

 acid radicals, the anhydrides are oxides. They are often formed by 

 abstracting water from two molecules of an acid, thus : 



C 2 H 3 O.Oin _ C 2 H 3 0\ , H0 

 C 2 H 3 O.OH/ - C 2 H30/ + H2 ' 



Amino-acids are compounds obtained from acids by replacement of 

 a hydrogen atom of the acid radical by NH 2 ; these compounds will 

 be spoken of later in connection with amides. 



Patty acids of the general composition, 

 C n H 2n 2 or C n H 2n + 1 C0 2 H. 



Occurs in : 



Fusing- Boiling- 

 point, point. 



Vegetable and animal fluids. 



Sweat, fluids of the stomach, etc. 



Butter. 



Valerian root. 



Butter. 



Castor oil. 



Butter ; cocoanut oil. 



Leaves of geranium. 



Butter. 



Cocoanut oil. 



Palm oil, butter. 

 (Obtained artificially.) 

 Most solid animal fats. 



Oils of certain plants. 

 Beeswax. 



The name fatty acids has been given to these acids on account of 

 their frequent occurrence in fats, and also in allusion to the some- 

 what fatty appearance of the higher members of the series. 



The gradual change of properties which the members of an homol- 

 ogous series show, is well marked in the series of fatty acids, thus : 



