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                      • ▸▸
                        • 🇬🇧 Holmium
                        • 🇨🇳 鈥
                        • 🇳🇱 Holmium
                        • 🇫🇷 Holmium
                        • 🇩🇪 Holmium
                        • 🇮🇱 הולמיום
                        • 🇮🇹 Olmio
                        • 🇯🇵 ホルミウム
                        • 🇵🇹 Hólmio
                        • 🇷🇺 Гольмий
                        • 🇪🇸 Holmio
                        • 🇸🇪 Holmium

                        Holmium: the essentials

                        Holmium atoms have 67 electrons and the shell structure is 2.8.18.29.8.2. The ground state electronic configuration of neutral holmium is [Xe].4f11.6s2 and the term symbol of holmium is 4I15/2.

                        Holmium: description  

                        Holmium is relatively soft and malleable, and is stable in dry air at room temperature. It oxidises rapidly in moist air and at elevated temperatures. The metal has unusual magnetic properties. The metal is a rare earth metal found in monazite, gadolinite and other minerals.

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

                        Holmium: physical properties

                        More physical properties...

                        Holmium: heat properties

                        More thermochemical properties...

                        Holmium: electronegativities

                        More electronegativity properties...

                        Holmium: orbital properties

                        More orbital properties...

                        Holmium: abundances

                        More geological data...

                        Holmium: crystal structure

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

                        More crystallographic data...

                        Holmium: biological data

                        网络斗地主下载Holmium has no biological role but is said to stimulate the metabolism.

                        More biological data...

                        Holmium: uses

                        Uses...

                        Holmium: reactions

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

                        View reactions of holmium...

                        Holmium: 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 holmium where known.

                        View binary compounds...

                        Holmium: compound properties

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

                        View compound properties...

                        Holmium: history

                        Holmium was discovered by J. L. Soret and Delafontaine in 1878 at Switzerland. Origin of name: from the Greek word "Holmia" meaning "Sweden".

                        More history...

                        Holmium: isotopes

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

                        More isotope and NMR data...

                        Holmium: isolation

                        Isolation: holmium 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 isolate 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 holmium is available through the reduction of HoF3 with calcium metal.

                        2HoF3 + 3Ca → 2Ho + 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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