A manual of elementary chemistry : theoretical and practical / by George Fownes.

  • Fownes, George, 1815-1849.
Date:
1873
Catalogue details

Licence: Public Domain Mark

Credit: A manual of elementary chemistry : theoretical and practical / by George Fownes. Source: Wellcome Collection.

    985/1062 (page 957)
    ALOES. 953 Morindin, O.,sIl30O1;-, is a yellow crystalline colouring matter, occurring in the root of Morinda citrifolia, called Soranjee in the East Indies. When heated it is converted into a beautiful crystalline body, morindone, containing CuH10O5. Aloes.—Certain of the products of the action, of nitric acid upon aloes very much resemble some of the derivatives of indigo, without, however, it seems, being identical with them. Powdered aloes, heated for a considerable time with excess of moderately strong nitric acid, yields a deep red solution, which, on cooling, deposits a yellow crystalline mass. This, purified by suitable means, constitutes ckrysarwrrdc acid: it crystallises in golden- yellow scales, which have a bitter taste, and are but sparingly soluble in water. Its potassium-salt has a carmine-red tint, and exhibits a green metallic lustre, like that of murexide. The formula of chrysamniic acid is not perfectly established. Ac- cording to Sfenhouse and Miiller,* it is probably C-H2N206 or C7H,(N02)202. Graebe and Liebermann,t on the other hand, regard chrysamniic acid as tetranitro-diomjanthraquinone, CY,!!,!^, = C14H2(N02)4(OH)2(0.2). Like picric acid, it yields cMoropicrin when treated with chloride of lime. The mother- liquor, from which the chrysammic acid has been deposited, con- tains a second acid, the chrysolcpic, which also forms golden-yellow, sparingly soluble, scaly crystals. The potassium-salt forms small yellow prisms, of httle solubility. It explodes by heat. Chry- solepic acid is perhaps identical with picric acid. To these may be added the styphnic, or oxypicric acid, pro- duced by the action of nitric acid of sp. gr. 1*2 upon assafcetida and several other gum resins and extracts. Brazil-wood and purree, when treated with excess of nitric acid, likewise yield styphnic acid. It crystallises, when pure, in slender, yellowish- white prisms, sparingly soluble in water, readily dissolved in alcohol and ether. It has a purely astringent taste, and stains the skin yellow. By a gentle heat it melts, and on cooling Incomes crystalline ; suddenly and strongly heated it burns Like gunpowder. It also yields chloropicrin. The salts of. this substance mostly crystallise in orange-yellow needles, and explode with great, violence by heat. Styphnic acid contains I !6H3N308, i.e., picric acid -f- 1 atom of oxygen. ♦ Journal of the Chemical Society [2], iv. 310. t Zeitschrift fiii- Chemie [2], iv. 503.