420 Action of Nitric Acid on Sebacic Acid. 



Art. XL. — On the Action of Nitric Acid on Sebacic Acid ; by 



Adolph Schlieper. 



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It is quoted in all chemical hand-books, that sebacic acid is not 

 altered by treatment with nitric acid ; but the similarity of many 

 of its physical properties with benzoic acid authorized the con- 

 jecture that, like the latter it might be converted into ?iitro-sebacic 

 acidC, H 7 :l N0 4 . In all cases it was interesting to know, if 

 the action of nitric acid on this constant product of decomposition 

 of oleic acid at high temperatures, did not cause the formation of 

 one or more of those acids which Laurent produced by direct 

 action on oleic acid by this agent. 



The sebacic acid employed in this research was obtained by 

 dry distillation of the crude commercial oleic acid. The distillate 

 was boiled with water several times, the watery extracts saturated 

 with carbonate of soda, and evaporated to dryness ; to remove 

 the caprylate and caprinate of soda; the dry saline mass was then 

 exhausted with hot absolute alcohol, which left the sebacate of 

 soda undissolved. The latter was then dissolved in water and the 

 sebacic acid precipitated by addition of muriatic acid ; after being 

 purified by several repeated crystallizations from water, it presented 

 itself as a loose, very light, white mass, consisting of small shin- 

 ing scales. 



To examine the formation of nitro-sebacic acid, one part of 

 sebacic acid was heated with 20-30 parts crude nitric acid, spec. 

 gr. 1*4, in a spacious matrass; no solution is effected when cold, 

 but it takes place perfectly a little below the boiling point ; at the 

 same time the orange colored vapors of hyponitrous acid and the 

 like color which the liquid assumes, indicate a decomposition of 

 the sebacic acid. The nitric solution was then kept at a continual 

 slow boiling on a sandbath, in such a manner that the evaporating 

 nitric acid condensed for the greater part in the long neck of the 



and flowed back. After 2-3 hours boiling, a small part 

 of the solution was poured out, to see if the formation of a nitro- 

 sebacic acid had taken place, though the continual but very slow 

 development of red vapors, indicated clearly, that the decompo- 

 sition was not yet finished. 



The hot nitric solution, mixed with 8-10 times its volume of 

 cold water, separated a great quantity of probably unaltered sebacic 

 acid, which having been washed out and dried, showed all the 

 physical properties of that substance. I prepared and analyzed 

 the silver salt of acid so obtained, and thus proved that it was 

 only unaltered sebacic acid. 0-312 grm. of the silver salt gave 

 0-161 grm. silver, which corresponds to an amount of oxyd of 

 silver of 5541 per cent. Sebacate of silver contains 55-76 per 

 cent, oxyd of silver. 



matrass 



