naphthalene (or ph as p)

[Eng. naphtha; I connect., and suff. -ene.] Chem.: C10H8 = C10H7H. Naphthalin, naphthaline. A frequent product of the dry distillation of organic substances, and occurring to a considerable extent in that portion of coal-tar distilling between 180° and 220°, from which it crystallizes on cooling. It forms colorle shining, leafy crystals of peculiar odor and burning taste; melts at 79° to a liquid as clear as water; boils at 216°-220°, and burns, when inflamed, with a highly luminous but smoky flame. Its specific gravity is '977 at the fusing point, and its vapor density=4 =4:53. It is insoluble in water, but di olves readily in alcohol, ether, chloroform, carbon disulphide, benzene, and fixed and volatile oils. Naphthalene unites directly with chlorine and bromine, forming a large number of substitution products. On pa ing dry chlorine gas into naphthalene, a heavy pale yellow oil is formed (naphthalene dichloride, C10H5Cl2), and this, unit ing with more chlorine, is converted into a crystalline substance (naphthalene tetrachloride, C10H8C14), which melts at 182. Monochlor-uaph thalene, C10H-Cl, obtained by heating naphthalene dichloride with alcoholic potash, is a colorle oil, boiling at 263°. Dichlor-naphthalene, C10H6C12, ic prepared by boiling naphthalene tetrachloride with alcoholic potash. It is a crystalline ma , melting at 35°-36°, and boiling at 280. The substitution products with bromine are far le stable than those of chlorine. naphthalene-alcohol, s. Chem.: C10H12O4=C10H8 HO4. A tetratomic alco naphthalene carboxylic-acid, subst. [NAPH THOIC-ACID.] naphthalene sulphonic-acid, s . Chem.: C10H7SO2 OH. Formed by heating naphthalene with concentrated sulphuric acid. If the temperature is kept low, alpha-naphthalene sulphonic acid is produced, melting at 85° to 90°; but if raised to 160°, the isomeric beta-naphthalene sul phonic acid is obtained. năph-thăl-Ic (or ph as p), a. [Eng. naphthal (ene); -ic.] Pertaining or derived from naphthalene. naphthalic-acid, s. Chem.: C12H3O4=C10H6(COOH)2. Obtained by the oxidation of ace naphthene by chromic and dilute sulphuric acids. It crystallizes in colorle needles or plates, which decompose at 140°. Calcic naphtha late yields naphthalene on heating with calcic hydrate, C10HCOOCa+Ca(OH)2=2(CaCO3) +C10H8.