化學科網頁
最 輕 的 金 屬Lithium :
Atomic Number 原子序: |
3 | Atomic Radius 原子半徑: |
152 pm | ||
Atomic Symbol 元素符號: |
Li | Melting Point 熔點: |
180.5 °C | ||
Relative Atomic Mass 相對原子質量 : |
6.941 | Boiling Point 沸點: |
1342 °C | ||
Electronic Configuration 電子組態 : |
[He]2s 1 | Oxidation States 氧化態 : |
1 |
History
(Gr. lithos : stone) Discovered by Arfvedson in 1817. Lithium is the lightest of all metals, with a density only about half that of water.
Sources
It does not occur freely in nature; combined, it is found in small units in nearly all igneous rocks and in many mineral springs. Lepidolite, spodumene, petalite, and amblygonite are the more important minerals containing it.
Lithium is presently being recovered from brines of Searles Lake, in California, and from those in Nevada. Large deposits of quadramene are found in North Carolina. The metal is produced electrolytically from the fused chloride. Lithium is silvery in appearance, much like Na, K, and other members of the alkali metal series. It reacts with water, but not as vigorously as sodium . Lithium imparts a beautiful crimson color to a flame, but when the metal burns strongly, the flame is a dazzling white.
Uses
Since World War II, the production of lithium metal and its compounds has increased greatly. Because the metal has the highest specific heat of any solid element, it has found use in heat transfer applications; however, it is corrosive and requires special handling. The metal has been used as an alloying agent, is of interest in synthesis of organic compounds, and has nuclear applications. It ranks as a leading contender as a battery anode material as it has a high electrochemical potential. Lithium is used in special glasses and ceramics. The glass for the 200-inch telescope at Mt. Palomar contains lithium as a minor ingredient. Lithium chloride is one of the most lyproscopic materials known, and it, as well as lithium bromide, is used in air conditioning and industrial drying systems. Lithium stearate is used as an all-purpose and high-temperature lubricant. Other lithium compounds are used in dry cells and storage batteries. Lithium carbide is used for the treatment of bipolar disease and other mental illness conditions.
Cost
The metal is priced at about $300/lb.
