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со скольки месяцев ребенок начинает узнавать близких, Lanthanum - Wikipedia, Lanthanum | Rare Earth Element, Uses in Technology, & Medicine | Britannica, Lanthanum Facts, Symbol, Discovery, Properties, Uses, Facts About Lanthanum - Live Science, Lanthanum (La) Element: Properties, Uses, Reactions, Effects, Lanthanum Facts – Atomic Number 57 or Symbol La, Comprehensive Guide to Lanthanum: Uses, Properties, and Applications.
Two occur in nature: stable lanthanum-139 (99.9119 percent) and very long-lived radioactive lanthanum-138 (0.0888 percent). A total of 38 of lanthanum (excluding nuclear isomers) have been characterized, ranging in mass from 117 to 155 and in half-life from 23.5 milliseconds (lanthanum-117) to 1.02 × 1011 years (lanthanum-138). The lanthanum-140 has been detected as a product in snow after nuclear test explosions.Lanthanum is concentrated commercially by crystallization of ammonium lanthanum nitrate. Ion-exchange and solvent extraction methods are used when high purity is desired. The metal is prepared by of fused anhydrous halides or by metallothermic reduction of its halides by or (e.g., reduction of the fluoride with ).Lanthanum exists in three allotropic (structural) forms. The α-phase is double close-packed hexagonal with a = 3.7740 Å and c = 12.171 Å at room temperature. The β-phase is face-centered cubic with a = 5.303 Å at 325 °C (617 °F). The γ-phase is body-centered cubic with a = 4.26 Å at 887 °C (1,629 °F).Highly purified lanthanum oxide is an ingredient in the manufacture of low-dispersion, high-refraction for components. Lanthanum is often used as LaNi5-based -storage and –metal hydride rechargeable in hybrid automobiles. Lanthanum is added to ferrous alloys (to scavenge , , and other impurities) and to nonferrous alloys such as superalloys, alloys, and alloys. Lanthanum compounds are used as hosts for in and detectors and in cracking , one of its major uses. (typically 50 percent cerium, 25 percent lanthanum, 18 percent , 5 percent , and 2 percent other rare earths) is primarily used for lighter flints and alloying additions. When combined with and , lanthanum forms cubic intermetallic compounds with a general La(Fe1−xSix)13 that exhibit the giant magnetocaloric effect. When those compounds are hydrogenated to about 1.2–1.5 hydrogen per formula unit, they have magnetic ordering temperatures near room temperature and, therefore, are useful as magnetic refrigeration materials for near-room-temperature applications., Lanthanum is a chemical element; it has symbol La and atomic number 57. It is a soft, ductile, silvery-white metal that tarnishes slowly when exposed to air. It is the eponym of the lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table, of which lanthanum is the first and the prototype. Lanthanum is traditionally counted among the rare earth , Lanthanum, chemical element, a rare-earth metal of Group 3 of the periodic table, that is the prototype of the lanthanide series of elements..
Lanthanum (pronunciation: LAN-the-nem) [3] is a soft, silvery rare-earth metal belonging to the lanthanoids family and represented by the chemical symbol La [1, 2]., Word origin: Lanthanum is named after the Greek word lanthanein, which means to escape notice. Discovery: Swedish chemist Carl Gustaf Mosander extracted lanthanum oxide, or lanthana, from an , Lanthanum is a chemical element with the atomic number 57 and is represented by the symbol ‘La’ in the periodic table. It is soft and silvery in appearance and classified as rare earth metal and belongs to the d-block of the lanthanide group of the periodic table. It is a highly reactive rare earth metal only behind europium. Similar to the majority of other rare earth elements, the , Get lanthanum facts. Discover the properties, uses, sources, and health effects of the element with atomic number 57 and element symbol La., Explore the comprehensive guide on Lanthanum, a rare-earth element with wide-ranging applications. Learn about its history, physical and chemical properties, industrial uses in fluid catalytic cracking, optics, and green technologies, as well as its medical applications. Understand its safety protocols and unique characteristics that make it essential in modern life., Lanthanum, with its unique physical and chemical properties, has become a cornerstone in various industrial applications. From catalysis and optics to electronics and medicine, the versatility of lanthanum continues to drive innovation and technological advancements..