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                              ▸▸
                              • 🇬🇧 Lanthanum
                              • 🇨🇳 鑭
                              • 🇳🇱 Lanthaan
                              • 🇫🇷 Lanthane
                              • 🇩🇪 Lanthan
                              • 🇮🇱 לנתן
                              • 🇮🇹 Lantanio
                              • 🇯🇵 ランタン
                              • 🇵🇹 Lantânio
                              • 🇷🇺 Лантан
                              • 🇪🇸 Lantano
                              • 🇸🇪 Lantan

                              Lanthanum: the essentials

                              Lanthanum atoms have 57 electrons and the shell structure is 2.8.18.18.9.2. The ground state electronic configuration of neutral lanthanum is [Xe].5d1.6s2 and the term symbol of lanthanum is 2D3/2.

                              Lanthanum: description  

                              网络斗地主下载Lanthanum is silvery white, malleable, ductile, and soft enough to be cut with a knife. It is one of the most reactive of the rare-earth metals. It oxidises rapidly when exposed to air. Cold water attacks lanthanum slowly, and hot water attacks it much more rapidly. The metal reacts directly with elemental carbon, nitrogen, boron, selenium, silicon, phosphorus, sulphur, and with halogens. It is a component of, misch metal (used for making lighter flints).

                              lanthanum
                              This sample is from , an attractive and safely packaged collection of the 92 naturally occurring elements that is available for sale.

                              Lanthanum: physical properties

                              More physical properties...

                              Lanthanum: heat properties

                              More thermochemical properties...

                              Lanthanum: atom sizes

                              More atomc size properties...

                              Lanthanum: electronegativities

                              More electronegativity properties...

                              Lanthanum: orbital properties

                              More orbital properties...

                              Lanthanum: abundances

                              More geological data...

                              Lanthanum: crystal structure

                              La crystal structure
                              The solid state structure of lanthanum is: bcc (body-centred cubic).

                              More crystallographic data...

                              Lanthanum: biological data

                              Lanthanum has no biological role.

                              More biological data...

                              Lanthanum: uses

                              Uses...

                              Lanthanum: reactions

                              网络斗地主下载 Reactions of lanthanum as the element with air, water, halogens, acids, and bases where known.

                              View reactions of lanthanum...

                              Lanthanum: binary compounds

                              网络斗地主下载 Binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and other compounds of lanthanum where known.

                              View binary compounds...

                              Lanthanum: compound properties

                              Bond strengths; lattice energies of lanthanum halides, hydrides, oxides (where known); and reduction potentials where known.

                              View compound properties...

                              Lanthanum: history

                              Lanthanum was discovered by Carl Gustaf Mosander in 1839 at Sweden. Origin of name: from the Greek word "lanthanein" meaning "to lie hidden".

                              More history...

                              Lanthanum: isotopes

                              Isotope abundances of lanthanum
                              Isotope abundances of lanthanum with the most intense signal set to 100%.

                              网络斗地主下载The two isotopes of Lanthanum do not appear to have many applications. Only La-139 is used for the production of the medical radioisotope Ce-139.

                              More isotope and NMR data...

                              Lanthanum: isolation

                              Isolation: lanthanum metal is available commercially so it is not normally necessary to make it in the laboratory, which is just as well as it is difficult to separate it from as the pure metal. This is largely because of the way it is found in nature. The lanthanoids are found in nature in a number of minerals. The most important are xenotime, monazite, and bastnaesite. The first two are orthophosphate minerals LnPO4 (Ln deonotes a mixture of all the lanthanoids except promethium which is vanishingly rare) and the third is a fluoride carbonate LnCO3F. Lanthanoids with even atomic numbers are more common. The most comon lanthanoids in these minerals are, in order, cerium, lanthanum, neodymium, and praseodymium. Monazite also contains thorium and ytrrium which makes handling difficult since thorium and its decomposition products are radioactive.

                              For many purposes it is not particularly necessary to separate the metals, but if separation into individual metals is required, the process is complex. Initially, the metals are extracted as salts from the ores by extraction with sulphuric acid (H2SO4), hydrochloric acid (HCl), and sodium hydroxide (NaOH). Modern purification techniques for these lanthanoid salt mixtures are ingenious and involve selective complexation techniques, solvent extractions, and ion exchange chromatography.

                              Pure lanthanum is available through the reduction of LaF3网络斗地主下载 with calcium metal.

                              2LaF3 + 3Ca → 2La + 3CaF2

                              This would work for the other calcium halides as well but the product CaF2 is easier to handle under the reaction conditions (heat to 50°C above the melting point of the element in an argon atmosphere). Excess calcium is removed from the reaction mixture under vacuum.

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