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      1. ▸▸
        • 🇬🇧 Niobium
        • 🇨🇳 鈮
        • 🇳🇱 Niobium
        • 🇫🇷 Niobium
        • 🇩🇪 Niob
        • 🇮🇱 ניוביום
        • 🇮🇹 Niobio
        • 🇯🇵 ニオブ
        • 🇵🇹 Nióbio
        • 🇷🇺 Ниобий
        • 🇪🇸 Niobio
        • 🇸🇪 Niob

        Niobium: the essentials

        Niobium atoms have 41 electrons and the shell structure is 2.8.18.12.1. The ground state electronic configuration of neutral niobium is [Kr].4d4.5s1 and the term symbol of niobium is 6D1/2.

        Niobium: description  

        The name niobium was adopted officially by IUPAC in 1950, but a few commercial producers still like to refer to it as columbium. Niobium is a shiny, white, soft, and ductile metal, and takes on a bluish tinge when exposed to air at room temperatures for a long time. The metal starts to oxidize in air at high temperatures, and when handled hot must be done so under a protective atmosphere so as to minimize oxide production.

        Niobium: physical properties

        More physical properties...

        Niobium: heat properties

        More thermochemical properties...

        Niobium: electronegativities

        More electronegativity properties...

        Niobium: orbital properties

        More orbital properties...

        Niobium: abundances

        More geological data...

        Niobium: crystal structure

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

        More crystallographic data...

        Niobium: biological data

        网络斗地主下载Niobium has no biological role.

        More biological data...

        Niobium: uses

        Uses...

        Niobium: reactions

        Reactions of niobium as the element with air, water, halogens, acids, and bases where known.

        View reactions of niobium...

        Niobium: binary compounds

        Binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and other compounds of niobium where known.

        View binary compounds...

        Niobium: compound properties

        网络斗地主下载 Bond strengths; lattice energies of niobium halides, hydrides, oxides (where known); and reduction potentials where known.

        View compound properties...

        Niobium: history

        Niobium was discovered by Charles Hatchett in 1801 at England. Origin of name: from the Greek word "Niobe" meaning "daughter of Tantalus" (tantalum is closely related to niobium in the periodic table).

        More history...

        Niobium: isotopes

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

        More isotope and NMR data...

        Niobium: isolation

        Isolation网络斗地主下载: isolation of niobium appears to be complicated. Niobium minerals usually contain both niobium and tantalum. Since they are so similar chemically, it is difficult to separate them. Niobium can be extracted from the ores by first fusing the ore with alkali, and then extracting the resultant mixture into hydrofluoric acid, HF. Current methodology involves the separation of tantalum from these acid solutions using a liquid-liquid extraction technique. In this process tantalum salts are extracted into the ketone MIBK (methyl isobutyl ketone, 4-methyl pentan-2-one). The niobium remains in the HF solution. Acidification of the HF solution followed by further extraction in MIBK gives an organic solution containing niobium.

        After conversion to the oxide, metallic niobium can be made by reduction with sodium or carbon. Electrolysis of molten fluorides is also used.

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