tha11um

[Etym. doubtful.] Min.: A name given to a supposed new element, which apparently has no existence. Chem. (pl.): Compounds formed by the action of thallium on alcohols, e. g ., Thallium-ethylate= C2H5TIO. Produced when thallium and ethylic alcohol are heated in a sealed tube to 100°. Being freed from exce of alcohol, it remains as an oil of specific gravity 3-48-3-55, being the heaviest liquid known except mercury. It di olves in five parts absolute alcohol, in pure ether, and chloroform. thallium-gla , s . A gla of great density and refracting power, in the preparation of which thallium is used instead of lead or pota ium. thallium-oxide, s. Chem.: Thallium forms two oxides: (1) Thallious oxide (protoxide), T120. Prepared by allowing the granulated metal to oxidize in moist air, boiling in distilled water, and repeating the proce two or three times. The hydrated oxide crystallizes out in yellow needles. The anhydrous oxide forms a reddish black ma , and is obtained by exposing the hydrated oxide in a vacuum over sulphuric acid. In water it forms a strongly alkaline solution, which di olves the skin and stains the nails a deep brown. Like potash, it decomposes the salts of the alkaline earths and metals. (2) Thallic oxide (peroxide), Tl2O3. The chief thal-lei-ô-chin, 8. [Formed from Gr. thallos product of burning the metal in oxygen. The anhy a green bud, and Peruv. quina =bark.] thăl-lēne, s. [Gr. thall (os); -ene.] Chem.: A solid hydrocarbon isomeric with anthracene obtained from the last products which pa over in the distillation of American petroleum. It is distinguished by a green fluorescence, and, when illuminated by violet and ultra-violet light, exhibits a fluorescent spectrum containing light-green bands. ( Watts : Sup .) thăl-lic, a. [Eng. thall (ium); -ic.] Pertaining to or containing thallium. thallic-chloride, s . [THALLIUM-CHLORIDE.]. thallic-oxide, s . [THALLIUM-OXIDE.] thăl-11-ous, a . [Eng. thalli (um); -ous.) Pertaining to thallium. thallious-chloride, s. [THALLIUM-CHLORIDE.] thallious-oxide, s. [THALLIUM-OXIDE.] thăl-lite, s. [Greek thallos =a twig; suff. ite ( Min .).] Min.: The same as OISANITE (q. v. thăl-11-ŭm, s . [Latinized from Gr. hallos a green bud, from the green line it gives in the spectrum, which led to its discovery.] Chemist.: Symbol Tl. Atomic weight 203-64. A triad metallic element discovered by Crookes in 1861, and widely distributed as a constituent in iron and copper pyrites, in blende, native sulphur, and in many kinds of ores. It can be distilled along with the sulphur by heating pyrites to a bright-red heat, then di olving out the exce of sulphur by boiling with caustic soda, collecting and washing the sulphide of thallium, converting it into sulphate, and precipitating the thallium in the metallic state by the action of pure metallic zinc. The spongy metal is compre ed, dried, and fused into a bright metallic button by heating under cyanide of pota ium. It is a perfect metal, with high luster, not quite so white as silver, but free from the chin, bench; go, gem; thin, this; drous oxide is a dark-brown powder, neutral to test paper, insoluble in water and alkalies, but di olves readily in acids, forming unstable salts. thallium-salts, s. pl. Chem. Both oxides form, with acids, definite and crystallizable salts, none of which is of much im. portance. thallium-triamine, s. Chem.: NTIH6. Known in combination as a hydro chlorate, N3TIH 3HCl, a compound formed by di olving thallic oxide in sal-ammoniac. By the action of water it is again resolved into thallie oxide and sal-ammoniac.