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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  

                                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
                                网络斗地主下载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

                                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%.

                                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 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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