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Gadolinium(III) Iodide
Gadolinium(III) iodide is an iodide of gadolinium, with the chemical formula of GdI3. It is a yellow, highly hygroscopic solid with a bismuth(III) iodide-type crystal structure. In air, it quickly absorbs moisture and forms hydrates. The corresponding oxide iodide is also readily formed at elevated temperature. Preparation Gadolinium(III) iodide can be obtained by reacting gadolinium with iodine:Georg Brauer (Hrsg.), unter Mitarbeit von Marianne Baudler u. a.: ''Handbuch der Präparativen Anorganischen Chemie.'' 3., umgearbeitete Auflage. Band I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6, S. 1077. :2 Gd + 3 I2 → 2 GdI3 It can also be obtained by reacting gadolinium with mercury(II) iodide in a vacuum at 500 °C: :2 Gd + 3 HgI2 → 2 GdI3 + 3 Hg Gadolinium(III) iodide can be obtained by the reaction between gadolinium(III) oxide and hydroiodic acid, crystallizing into the hydrate form. The hydrate form can be heated with ammonium iodide to form the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gadolinium(III) Fluoride
Gadolinium(III) fluoride is an inorganic compound with a chemical formula GdF3. Preparation Gadolinium(III) fluoride can be prepared by heating gadolinium oxide and ammonium bifluoride. The reaction involves two steps: : Gd2O3 + 6 NH4HF2 → 2 NH4GdF4 + 4 NH4F + 3 H2O : NH4GdF4 → GdF3 + NH3 + HF Alternatively, reacting gadolinium chloride with hydrofluoric acid and adding hot water produces GdF3·xH2O (x＝0.53). Anhydrous gadolinium(III) fluoride can then be produced by heating the hydrate with ammonium bifluoride; without the bifluoride, GdOF is formed instead. : GdCl3 + 3 HF + x H2O → GdF3·xH2O + 3 HCl Properties Gadolinium(III) fluoride is a white solid that is insoluble in water. It has an orthorhombic crystal structure with the space group Pnma (space group no. 62). Uses Gadolinium(III) fluoride is used to produce fluoride glass Fluoride glass is a class of non-oxide optical glasses composed of fluorides of various metals. They can contain heavy metals suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georg Brauer
Georg Karl Brauer (born 11. April 1908 in Bochum, died 26. February 2001 in Freiburg im Breisgau) was a German chemist. Life Brauer was the son of the chemist Eberhard Brauer and Elisabeth Brauer, a daughter of Wilhelm Ostwald. From 1926 to 1932, Brauer studied in Leipzig and Freiburg. He received his doctorate under supervision of Eduard Zintl Eduard Zintl (21 January 1898 – 17 January 1941) was a German chemist. He gained prominence for research on intermetallic compounds. Family background After his family moved from Weiden and Bayreuth to Munich and after he had finished school ... in Freiburg in 1933. In 1941, he received is habilitation at the TH Darmstadt. In 1946, he became an extraordinary professor in Freiburg. From 1959 to 1976, he was a full professor. Starting in 1976, he was a emeritus professor. Research Brauer's research included the chemistry and crystal chemistry of intermetallic compounds and alloys. He investigated binary systems of transition metal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gadolinium Compounds
Gadolinium is a chemical element with the symbol Gd and atomic number 64. Gadolinium is a silvery-white metal when oxidation is removed. It is only slightly malleable and is a ductile rare-earth element. Gadolinium reacts with atmospheric oxygen or moisture slowly to form a black coating. Gadolinium below its Curie point of is ferromagnetic, with an attraction to a magnetic field higher than that of nickel. Above this temperature it is the most paramagnetic element. It is found in nature only in an oxidized form. When separated, it usually has impurities of the other rare-earths because of their similar chemical properties. Gadolinium was discovered in 1880 by Jean Charles de Marignac, who detected its oxide by using spectroscopy. It is named after the mineral gadolinite, one of the minerals in which gadolinium is found, itself named for the Finnish chemist Johan Gadolin. Pure gadolinium was first isolated by the chemist Paul-Émile Lecoq de Boisbaudran around 1886. Gadoliniu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tantalum
Tantalum is a chemical element with the symbol Ta and atomic number 73. Previously known as ''tantalium'', it is named after Tantalus, a villain in Greek mythology. Tantalum is a very hard, ductile, lustrous, blue-gray transition metal that is highly corrosion-resistant. It is part of the refractory metals group, which are widely used as components of strong high-melting-point alloys. It is a group 5 element, along with vanadium and niobium, and it always occurs in geologic sources together with the chemically similar niobium, mainly in the mineral groups tantalite, columbite and coltan. The chemical inertness and very high melting point of tantalum make it valuable for laboratory and industrial equipment such as reaction vessels and vacuum furnaces. It is used in tantalum capacitors for electronic equipment such as computers. Tantalum is considered a technology-critical element by the European Commission. History Tantalum was discovered in Sweden in 1802 by Anders Ekeberg, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gadolinium Nitride
Gadolinium(III) nitride is a binary inorganic compound of gadolinium and nitrogen with the chemical formula . Preparation Gadolinium(III) nitride can be prepared by the direct reaction of gadolinium metal and nitrogen gas at 1600 °C and at a pressure of 1300 atm. : Properties Physical Gadolinium(III) nitride forms a black powder. It is isomorphous with sodium chloride with the space group of Fmm. Chemical Gadolinium(III) nitride hydrolyzes in humid air to form gadolinium(III) hydroxide and ammonia. It is insoluble in water Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ... but soluble in acids. Uses Gadolinium(III) nitride is used as a semiconductor. It can also be used as a magnetic material, a catalyst in chemical reactions and a component in neutron conve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Description The combining capacity, or affinity of an ...—its atom making four electrons available to form covalent bond, covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three Isotopes of carbon, isotopes occur naturally, Carbon-12, C and Carbon-13, C being stable, while Carbon-14, C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the Timeline of chemical element discoveries#Ancient discoveries, few elements known since antiquity. Carbon is the 15th Abundance of elements in Earth's crust, most abundant element in the Earth's crust, and the Abundance of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argon
Argon is a chemical element with the symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third-most abundant gas in Earth's atmosphere, at 0.934% (9340 ppmv). It is more than twice as abundant as water vapor (which averages about 4000 ppmv, but varies greatly), 23 times as abundant as carbon dioxide (400 ppmv), and more than 500 times as abundant as neon (18 ppmv). Argon is the most abundant noble gas in Earth's crust, comprising 0.00015% of the crust. Nearly all of the argon in Earth's atmosphere is radiogenic argon-40, derived from the decay of potassium-40 in Earth's crust. In the universe, argon-36 is by far the most common argon isotope, as it is the most easily produced by stellar nucleosynthesis in supernovas. The name "argon" is derived from the Greek word , neuter singular form of meaning 'lazy' or 'inactive', as a reference to the fact that the element undergoes almost no chemical reactions. The complete octe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table. In some respects, zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size.The elements are from different metal groups. See periodic table. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity ( electrowinning). Zinc is an essential trace element for humans, animals, plants and for microorganisms and is necessary for prenatal and postnatal development. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Iodide
Ammonium iodide is the chemical compound NH4I. It is used in photographic chemicals and some medications.Holleman, A. F.; Wiberg, E. ''Inorganic Chemistry'' Academic Press: San Diego, 2001. . It can be prepared by the action of hydroiodic acid on ammonia. It is easily soluble in water, from which it crystallizes in cubes. It is also soluble in ethanol. It gradually turns yellow on standing in moist air, owing to decomposition with liberation of iodine. Preparation Ammonium iodide can be made in lab by reacting ammonia or ammonium hydroxide with hydroiodic acid or hydrogen iodide gas: : NH3 + HI → NH4I : NH4OH + HI → NH4I + H2O It is also formed by the decomposition of ammoniated nitrogen triiodide Nitrogen triiodide is an inorganic compound with the formula N I3. It is an extremely sensitive contact explosive: small quantities explode with a loud, sharp snap when touched even lightly, releasing a purple cloud of iodine vapor; it can even b ... (an explosive). Referenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroiodic Acid
Hydroiodic acid (or hydriodic acid) is an aqueous solution of hydrogen iodide (HI). It is a strong acid, one that is ionized completely in an aqueous solution. It is colorless. Concentrated solutions are usually 48% to 57% HI. Reactions Hydroiodic acid reacts with oxygen in air to give iodine: :4 HI + O2 → 2 + 2 I2 Like other hydrogen halides, hydroiodic acid adds to alkenes to give alkyl iodides. It can also be used as a reducing agent, for example in the reduction of aromatic nitro compounds to anilines. Cativa process The Cativa process is a major end use of hydroiodic acid, which serves as a co-catalyst for the production of acetic acid by the carbonylation of methanol. Illicit uses Hydroiodic acid is listed as a U.S. Federal DEA List I Chemical, owing to its use as a reducing agent related to the production of methamphetamine from ephedrine Ephedrine is a central nervous system (CNS) stimulant that is often used to prevent low blood pressure during anesthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gadolinium(III) Oxide
Gadolinium(III) oxide (archaically gadolinia) is an inorganic compound with the formula Gd2O3. It is one of the most commonly available forms of the rare-earth element gadolinium, derivatives of which are potential contrast agents for magnetic resonance imaging. Structure Gadolinium oxide adopts two structures. The cubic ( cI80, Ia), No. 206) structure is similar to that of manganese(III) oxide and heavy trivalent lanthanide sesquioxides. The cubic structure features two types of gadolinium sites, each with a coordination number of 6 but with different coordination geometries. The second polymorph is monoclinic (Pearson symbol mS30, space group C2/m, No. 12). At room temperature, the cubic structure is more stable. The phase change to the monoclinic structure takes place at 1200 °C. Above 2100 °C to the melting point at 2420 °C, a hexagonal phase dominates. Preparation and chemistry Gadolinium oxide can be formed by thermal decomposition of the hydroxide, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury(II) Iodide
Mercury(II) iodide is a chemical compound with the molecular formula Hg I2. It is typically produced synthetically but can also be found in nature as the extremely rare mineral coccinite. Unlike the related mercury(II) chloride it is hardly soluble in water (<100 ppm). Production Mercury(II) iodide is produced by adding an aqueous solution of to an aqueous solution of with stirring; the precipitate is filtered off, washed and dried at 70 °C. : HgCl2 + 2 KI → HgI2 + 2 KClProperties Mercury(II) iodide displays |
