164 



acids, and are best separated by means of partial crys- 

 tallization from ethereal solutions ; they are produced 

 further by the action of fuming nitric acid on palmi- 

 tolic acid and the acids homologous to it. In the 

 latter case an acid is always formed, containing half 

 as many carbon atoms as that from which it results; 

 from palmitolic acid is obtained suberic acid ; from 

 stearolic acid, azelaic acid ; and from behenolic, brassy- 

 lie acid. 



5. Adipic acid, C 6 H 10 4 . Is produced from 3-iodo- 

 propionic acid by heating with finely divided silver to 

 120-130 ; and by the action of nascent hydrogen on 

 muconic acid (see Mucic Acid) ; is prepared most readily 

 by boiling sebacic acid with nitric acid, and separating 

 it from succinic acid, which is formed at the same time 

 by recrystallizing from alcohol. Laminae with a vitre- 

 ous lustre, or flattened prisms; easily soluble in hot 

 water, alcohol, and ether ; fusing point, 148. 



A syrupy acid isomeric with this is obtained in the 

 same way from a-brompropionic acid. 



6. Suberic acid, C 8 H 14 4 , is also formed, when cork 

 is treated for a long time with nitric acid. Needles or 

 plates, often an inch in length. But slightly soluble 

 in cold water and ether ; easily soluble in alcohol. 

 Fusing point, 140. When heated with barium hy- 

 droxide, hexyl hydride is formed. 



Suberic aldehyde, C 8 H 14 3 , is formed, together with 

 suberic acid, by the action of fuming nitric acid on 

 palmitolic acid. Thick oil, boiling at 202, at the 

 same time undergoing decomposition. 



7. Azelaic acid (Lepargylic acid), C 9 H 16 4 . Large 

 laminse or flattened needles. Yery difficultly soluble 

 in cold water, easily soluble in hot water, ether, and 

 alcohol. Fusing point, 106; gives heptyl hydride, 

 when heated with barium hydroxide. 



8. Sebacic acid, C 10 H 18 4 , is best obtained by boiling 

 spermaceti or stearic acid with an equal weight of 



