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Elements of chemistry, including the actual state and prevalent doctrines of the science / By the late Edward Turner.

  • Edward Turner
Date:
1847
Catalogue details

Licence: Public Domain Mark

Credit: Elements of chemistry, including the actual state and prevalent doctrines of the science / By the late Edward Turner. Source: Wellcome Collection.

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    1076 ROCCELLIC ACID. camphor, and in the oils of valerian and sage, all of which yield, by oxidation, ordinary camphor. In most of its external properties Borneo camphor, or Borneole, as Gerhardt names it, is similar to the ordinary species of camphor. (ENANTHIC ACID. Formula of the anhydrous acid, C14H1302. Formula of the hydrated acid, CuH1302,H0. (Pelouze and Liebig.) This acid occurs in most fermented liquors, especially in wine and corn spirit, combined with oxide of ethyle. When wine is distilled, this compound passes over at the end of the process in small quantity. By digestion with potash, oenanthate of potash is obtained, and from this salt the acid is separated by sulphuric acid, in the form of an oily liquid, which rises to the surface. At 54° it is semi-solid. It has neither taste nor smell; is insoluble in water, soluble in alcohol and ether. In this state it is the hydrated acid. When distilled, it is resolved into water and anhydrous acid. Of the salts of cenanthic acid only the oenanthate of oxide of ethyle is well known. This is the oil obtained by distilling wine or other fermented liquors, at the end of the distillation. It is purified from a little free cenanthic acid by heating it with a weak solution of carbonate of potash, when the pure oil rises to the sui-face. Its formula is C18H1803 = C14H1302 -I- C4H50. (Pelouze and Liebig ; Mulder.) It is a mobile, oilv colourless liquid, having a strong smell of wine. Sp. gr. 0’862. It boil at 435°. By the action of potash it is resolved into cenanthic acid and alcohol. It is to be observed, that this singular compound is not the cause of that peculiar fragrance in certain wines which is called the bouquet or aroma ; but, on the contrary, of that somewhat unpleasant smell which is found in every kind of wine, and which is so characteristic, that we can always tell by it whether a bottle or cask has been used for containing wine, even when the vessel has been for some time empty. ROCCELLIC ACID. Formula of the crystallized acid, C,rHl604. (Liebig.) Discovered in Rocella tinctoria by Heeren. It is extracted from the lichen by ammonia, and the solution precipitated by chloride of calcium. The roceellate of lime is decomposed by weak hydrochloric acid, when the roccellic acid separates. It is purified by solution in ether and crys¬ tallization. It forms fine white needles, fusible about 295°. In its