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Promethium(III) Bromide
Promethium(III) bromide is an inorganic compound, with the chemical formula of PmBr3. It is radioactive salt. It is a crystal of the hexagonal crystal system, with the space group of P63/mc (No. 176). Preparation Promethium(III) bromide can be obtained by reacting hydrogen bromide and promethium(III) oxide Promethium(III) oxide is a compound with the formula Pm2O3. It is the most common form of promethium. Crystal structure Promethium oxide exists in three major crystalline forms: *a, b and c are lattice parameters, Z is the number of formula ...: : Pm2O3 + 6 HBr —500°C→ 2 PmBr3 + 3 H2O Promethium(III) bromide hydrate cannot be heated to form its anhydrous form. Instead it decomposes in water to form promethium oxybromide: : PmBr3 + H2O(g) → PmOBr + 2 HBr References {{Lanthanide halides category:Bromides category:Promethium compounds Lanthanide halides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promethium(III) Fluoride
Promethium(III) fluoride or promethium trifluoride is a salt of promethium and fluorine with the formula PmF3. Promethium(III) fluoride is sparingly soluble in water. It reacts with metallic lithium to yield lithium fluoride Lithium fluoride is an inorganic compound with the chemical formula LiF. It is a colorless solid that transitions to white with decreasing crystal size. Its structure is analogous to that of sodium chloride, but it is much less soluble in water. ... and metallic promethium: : References Promethium compounds Fluorides Lanthanide halides {{Metal-halide-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promethium(III) Chloride
Promethium(III) chloride is a chemical compound of promethium and chlorine with the formula PmCl3. It is an ionic, water soluble, crystalline salt that glows in the dark with a pale blue or green light due to promethium's intense radioactivity. Preparation Promethium(III) chloride is obtained from promethium(III) oxide by heating it in a stream of dry HCl at 580 °C. Properties Promethium(III) chloride is a purple solid with a melting point of 655 °C. It crystallizes in the hexagonal crystal system (NdCl3 type) with the lattice parameters ''a'' = 739 pm and ''c'' = 421 pm with two formula units per unit cell and thus a calculated density of 4.19 g·cm−3.Weigel: ''Die Chemie des Promethiums'', p. 588–589.''Gmelins Handbuch der anorganischen Chemie'', System No. 39, p. 181. When PmCl3 is heated in the presence of H2O, the pale pink colored promethium(III) oxychloride (PmOCl) is obtained.''Gmelins Handbuch der anorganischen Chemie'', System No. 39 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promethium(III) Iodide
Promethium(III) iodide is an inorganic compound, with the chemical formula of PmI3. It is a red radioactive solid with a melting point of 695 °C. Preparation Promethium(III) iodide is obtained by reacting anhydrous hydrogen iodide and promethium(III) chloride at a high temperature: : PmCl3 + 3 HI → PmI3 + 3 HCl From the reaction of a HI-H2 mixture and promethium oxide (Pm2O3), promethium(III) iodide cannot be produced, and only promethium oxyiodide (PmOI) can be obtained. Promethium oxide reacts with molten aluminum iodide Aluminium iodide is a chemical compound containing aluminium and iodine. Invariably, the name refers to a compound of the composition , formed by the reaction of aluminium and iodine or the action of on metal. The hexahydrate is obtained fr ... at 500 °C to form promethium iodide. more complete reference required References Iodides Promethium compounds Lanthanide halides {{Metal-halide-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neodymium(III) Bromide
Neodymium(III) bromide is an inorganic salt of bromine and neodymium the formula NdBr3. The anhydrous compound is an off-white to pale green solid at room temperature, with an orthorhombic PuBr3-type crystal structure. The material is hygroscopicDavid R. Lide (Hrsg.): ''CRC Handbook of Chemistry and Physics.'' 90. Auflage. (Internet-Version: 2010), CRC Press/Taylor and Francis, Boca Raton, FL, ''Properties of the Elements and Inorganic Compounds,'' S. 4-77. and forms a hexahydrate in water (NdBr3· 6H2O), similar to the related neodymium(III) chloride. Preparation The direct reaction of neodymium with bromine can create neodymium(III) bromide: :2Nd + 3Br2 → 2NdBr3 In the presence of carbon, neodymium(III) oxide reacts with carbon tetrabromide to produce neodymium(III) bromide. Structure Neodymium(III) bromide adopts the plutonium(III) bromide crystal structure. The neodymium ions are 8-coordinate and adopt a bicapped trigonal prismatic geometry. The neodymium–bromine b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samarium(III) Bromide
Samarium(III) bromide is a crystalline compound of one samarium and three bromine atoms with the chemical formula of SmBr3. The compound has a crystal structure isotypic to that of plutonium(III) bromide. Preparation SmBr3·6H2O can be crystallized by dissolving samarium oxide in 40% hydrobromic acid. The hydrate and ammonium bromide are heated in a vacuum to obtain the anhydrous form of samarium(III) bromide.林平娣, 吴国庆无水三溴化钐和三溴化镱的制备 化学试剂, 1991(1):13-14. Other compounds Samarium(III) bromide forms some compounds with hydrazine, such as SmBr3·3N2H4·H2O which is a pale yellow needle-shaped crystal that is soluble in water and ethanol but insoluble in benzene Benzene is an Organic compound, organic chemical compound with the Chemical formula#Molecular formula, molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal Ring (chemistry), ring with one hyd ..., with d20 °C = 3.147 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep Mantle (geology), mantle remain active areas of investigation. All allotropes (structurally different pure forms of an element) and some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, graphene, etc.), carbon monoxide , carbon dioxide , carbides, and salt (chemistry), salts of inorganic anions such as carbonates, cyanides, cyanates, thiocyanates, isothiocyanates, etc. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it cannot occur within life, living things. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Formula
A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and ''plus'' (+) and ''minus'' (−) signs. These are limited to a single typographic line of symbols, which may include subscripts and superscripts. A chemical formula is not a chemical name since it does not contain any words. Although a chemical formula may imply certain simple chemical structures, it is not the same as a full chemical structural formula. Chemical formulae can fully specify the structure of only the simplest of molecules and chemical substances, and are generally more limited in power than chemical names and structural formulae. The simplest types of chemical formulae are called '' empirical formulae'', which use letters and numbers indicating the numerical ''proportions'' of atoms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexagonal Crystal System
In crystallography, the hexagonal crystal family is one of the six crystal family, crystal families, which includes two crystal systems (hexagonal and trigonal) and two lattice systems (hexagonal and rhombohedral). While commonly confused, the trigonal crystal system and the rhombohedral lattice system are not equivalent (see section hexagonal crystal family#Crystal systems, crystal systems below). In particular, there are crystals that have trigonal symmetry but belong to the hexagonal lattice (such as α-quartz). The hexagonal crystal family consists of the 12 point groups such that at least one of their space groups has the hexagonal lattice as underlying lattice, and is the union of the hexagonal crystal system and the trigonal crystal system. There are 52 space groups associated with it, which are exactly those whose Bravais lattice is either hexagonal or rhombohedral. __TOC__ Lattice systems The hexagonal crystal family consists of two lattice systems: hexagonal and rhom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Group
In mathematics, physics and chemistry, a space group is the symmetry group of a repeating pattern in space, usually in three dimensions. The elements of a space group (its symmetry operations) are the rigid transformations of the pattern that leave it unchanged. In three dimensions, space groups are classified into 219 distinct types, or 230 types if chiral copies are considered distinct. Space groups are discrete cocompact groups of isometries of an oriented Euclidean space in any number of dimensions. In dimensions other than 3, they are sometimes called Bieberbach groups. In crystallography, space groups are also called the crystallographic or Fedorov groups, and represent a description of the symmetry of the crystal. A definitive source regarding 3-dimensional space groups is the ''International Tables for Crystallography'' . History Space groups in 2 dimensions are the 17 wallpaper groups which have been known for several centuries, though the proof that the list ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Bromide
Hydrogen bromide is the inorganic compound with the formula . It is a hydrogen halide consisting of hydrogen and bromine. A colorless gas, it dissolves in water, forming hydrobromic acid, which is saturated at 68.85% HBr by weight at room temperature. Aqueous solutions that are 47.6% HBr by mass form a constant-boiling azeotrope mixture that boils at . Boiling less concentrated solutions releases H2O until the constant-boiling mixture composition is reached. Hydrogen bromide, and its aqueous solution, hydrobromic acid, are commonly used reagents in the preparation of bromide compounds. Reactions Organic chemistry Hydrogen bromide and hydrobromic acid are important reagents in the production of organobromine compounds.Greenwood, N. N.; Earnshaw, A. Chemistry of the Elements; Butterworth-Heineman: Oxford, Great Britain; 1997; pp. 809–812.Vollhardt, K. P. C.; Neil E. Schore, Schore, N. E. Organic Chemistry: Structure and Function; 4th Ed.; W. H. Freeman and Company: New York, N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promethium(III) Oxide
Promethium(III) oxide is a compound with the formula Pm2O3. It is the most common form of promethium. Crystal structure Promethium oxide exists in three major crystalline forms: *a, b and c are lattice parameters, Z is the number of formula units per unit cell, density is calculated from X-ray data. The low-temperature cubic form converts to the monoclinic structure upon heating to 750–800 °C, and this transition can only be reversed by melting the oxide. The transition from the monoclinic to hexagonal form occurs at 1740 °C. References Promethium compounds Sesquioxides {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromides
A bromide ion is the negatively charged form (Br−) of the element bromine, a member of the halogens group on the periodic table. Most bromides are colorless. Bromides have many practical roles, being found in anticonvulsants, flame-retardant materials, and cell stains. Although uncommon, chronic toxicity from bromide can result in bromism, a syndrome with multiple neurological symptoms. Bromide toxicity can also cause a type of skin eruption, see potassium bromide. The bromide ion has an ionic radius of 196 pm. Natural occurrence Bromide is present in typical seawater (35 PSU) with a concentration of around 65 mg/L, which is about 0.2% of all dissolved salts. Seafood and deep sea plants generally have higher levels than land-derived foods. Bromargyrite—natural, crystalline silver bromide—is the most common bromide mineral known but is still very rare. In addition to silver, bromine is also in minerals combined with mercury and copper. Formation and re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
