碲 -—— 元素描述（Tellurium - element description）.docVIP

碲 -—— 元素描述（Tellurium - element description） Tellurium element description There are two kinds of crystalline and amorphous allotropes. The ionization energy is 9.009 ev. Crystalline tellurium has a silvery white metallic appearance with a density of 6.25 g / cm 3, a melting point of 452 DEG C, a boiling point of 1390 DEG C, and a hardness of 2.5 (Mohs hardness). Not soluble in any solvent that does not react with it. The molecular weight of the solvent at room temperature is still unknown. Amorphous tellurium (brown), density 6 g / cm 3, melting point 449.5 + 0.3 DEG C, boiling point 989.8 + 3.8 DEG C. Tellurium burns in air and has a blue flame, producing two tellurium. It reacts with halogen but not reacts with sulfur and selenium. Soluble in sulfuric acid, nitric acid, potassium hydroxide and potassium cyanide solution. Easy to conduct and conduct electricity. Tellurium - Discovery Tellurium (TE) In 1782 the German mineralogist Miller von Reichenstein?? in the study of German gold ore, an unknown substance. In 1798, the German Tellus confirmed the discovery and measured the properties of the substance, named tellurium in latin. Tellurium has an alloy in nature with gold. In 1782, a mine supervisor in Austria, the capital of Vienna, extracted tellurium from the ore, originally mistaken for antimony, and later discovered that it is different from antimony and is therefore a new metal element. In order to obtain confirmation from others, Mou sent a few samples to Swedish chemist Bergman, asking him to identify them. Since the number of samples was too small, Bergman could only prove that it was not antimony. Le Mou find overlooked 16 years after January 25, 1798, klaproth in Berlin Academy of Sciences read an article on the Transylvanian gold paper, to put this forgotten element. He dissolved the ore in Wang Shuizhong, precipitated it with some excess alkali, removed gold and iron, and found the new element in the sediment, named tellurium (tellurium), and the eleme