|
Gadolinium(III) Bromide
Gadolinium(III) bromide is a crystalline compound of gadolinium atoms and three bromine atoms. This salt is hygroscopic. Preparation Gadolinium(III) bromide can be obtained by the reaction between gadolinium and hydrobromic acid: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. :\mathrm The anhydrous form can be obtained by heating the hydrate with ammonium bromide Ammonium bromide, NH4Br, is the ammonium salt of hydrobromic acid. The chemical crystallizes in colorless prisms, possessing a saline taste; it sublimes on heating and is easily soluble in water. On exposure to air it gradually assumes a yellow c .... References {{Lanthanide halides Bromides Gadolinium compounds Lanthanide halides ... [...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] |
Gadolinium(III) Chloride
Gadolinium(III) chloride, also known as gadolinium trichloride, is GdCl3. It is a colorless, hygroscopic, water-soluble solid. The hexahydrate GdCl3∙6H2O is commonly encountered and is sometimes also called gadolinium trichloride. Gd3+ species are of special interest because the ion has the maximum number of unpaired spins possible, at least for known elements. With seven valence electrons and seven available f-orbitals, all seven electrons are unpaired and symmetrically arranged around the metal. The high magnetism and high symmetry combine to make Gd3+ a useful component in NMR spectroscopy and MRI. Preparation GdCl3 is usually prepared by the " ammonium chloride" route, which involves the initial synthesis of (NH4)2 dCl5 This material can be prepared from the common starting materials at reaction temperatures of 230 °C from gadolinium oxide: ::10 NH4Cl + Gd2O3 → 2 (NH4)2 dCl5 + 6 NH3 + 3 H2O from hydrated gadolinium chloride: ::4 NH4Cl + 2 GdCl3∙6H2O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gadolinium
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] |
Bromine
Bromine is a chemical element with the symbol Br and atomic number 35. It is the third-lightest element in group 17 of the periodic table (halogens) and is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig (in 1825) and Antoine Jérôme Balard (in 1826), its name was derived from the Ancient Greek (bromos) meaning "stench", referring to its sharp and pungent smell. Elemental bromine is very reactive and thus does not occur as a native element in nature but it occurs in colourless soluble crystalline mineral halide salts, analogous to table salt. In fact, bromine and all the halogens are so reactive that they form bonds in pairs—never in single atoms. While it is rather rare in the Earth's crust, the high solubility of the bromide ion (Br) has caused its accumulation in the oceans. Commercial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hygroscopy
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption or adsorption from the surrounding environment, which is usually at normal or room temperature. If water molecules become suspended among the substance's molecules, adsorbing substances can become physically changed, e.g., changing in volume, boiling point, viscosity or some other physical characteristic or property of the substance. For example, a finely dispersed hygroscopic powder, such as a salt, may become clumpy over time due to collection of moisture from the surrounding environment. ''Deliquescent'' materials are sufficiently hygroscopic that they absorb so much water that they become liquid and form an aqueous solution. Etymology and pronunciation The word ''hygroscopy'' () uses combining forms of '' hygro-'' and '' -scopy''. Unlike any other ''-scopy'' word, it no longer refers to a viewing or imaging mode. It did begin that way, with the word ''hygroscope'' referring in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
