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Rubidium Bromide
Rubidium bromide is the bromide of rubidium. It has a NaCl crystal structure, with a lattice constant of 685 picometres. There are several methods for synthesising rubidium bromide. One involves reacting rubidium hydroxide with hydrobromic acid Hydrobromic acid is a strong acid formed by dissolving the diatomic molecule hydrogen bromide (HBr) in water. "Constant boiling" hydrobromic acid is an aqueous solution that distills at and contains 47.6% HBr by mass, which is 8.77 mol/L. ...: :RbOH + HBr → RbBr + H2O Another method is to neutralize rubidium carbonate with hydrobromic acid: :Rb2CO3 + 2 HBr → 2 RbBr + H2O + CO2 Rubidium metal would react directly with bromine to form RbBr, but this is not a sensible production method, since rubidium metal is substantially more expensive than the carbonate or hydroxide; moreover, the reaction would be explosive. References WebElements URL accessed March 1, 2006. Rubidium compounds Bromides Metal halides Alkali me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Fluoride
Rubidium fluoride (RbF) is the fluoride salt of rubidium. It is a cubic crystal with rock-salt structure. There are several methods for synthesising rubidium fluoride. One involves reacting rubidium hydroxide with hydrofluoric acid: :RbOH + HF → RbF + H2O Another method is to neutralize rubidium carbonate with hydrofluoric acid: :Rb2CO3 + 2HF → 2RbF + H2O + CO2 Another possible method is to react rubidium hydroxide with ammonium fluoride: :RbOH + NH4F → RbF + H2O + NH3 The least used method due to expense of rubidium metal is to react it directly with fluorine gas, as rubidium reacts violently with halogen The halogens () are a group in the periodic table consisting of five or six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts). In the modern IUPAC nomenclature, this group is ...s: :2Rb + F2 → 2RbF References * Rubidium compounds Fluorides Alkali metal fluorides Rock salt crystal struct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium
Rubidium is the chemical element with the symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years—more than three times as long as the estimated age of the universe. German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. The name comes from the Latin word , meaning deep red, the color of its emission spectrum. Rubidium's compounds have various chemical and electronic applications. Rubidium metal is easily vaporized and has a convenient spectral absorption range, making it a frequent target for laser manipulation of atoms. Rubidium is not a known nutrient for any living organisms. However, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal Halides
Metal halides are compounds between metals and halogens. Some, such as sodium chloride are ionic, while others are covalently bonded. A few metal halides are discrete molecules, such as uranium hexafluoride, but most adopt polymeric structures, such as palladium chloride. File:NaCl polyhedra.png, Sodium chloride crystal structure File:Uranium-hexafluoride-unit-cell-3D-balls.png, Discrete UF6 molecules File:Alpha-palladium(II)-chloride-xtal-3D-balls.png, Infinite chains of one form of palladium chloride Preparation The halogens can all react with metals to form metal halides according to the following equation: :2M + nX2 → 2MXn where M is the metal, X is the halogen, and MXn is the metal halide. In practice, this type of reaction may be very exothermic, hence impractical as a preparative technique. Additionally, many transition metals can adopt multiple oxidation states, which complicates matters. As the halogens are strong oxidizers, direct combination of the elements usua ... [...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 react ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Compounds
Rubidium is the chemical element with the symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years—more than three times as long as the estimated age of the universe. German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. The name comes from the Latin word , meaning deep red, the color of its emission spectrum. Rubidium's compounds have various chemical and electronic applications. Rubidium metal is easily vaporized and has a convenient spectral absorption range, making it a frequent target for laser manipulation of atoms. Rubidium is not a known nutrient for any living organisms. However, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Carbonate
Rubidium carbonate, Rb2CO3, is a convenient compound of rubidium; it is stable, not particularly reactive, and readily soluble in water, and is the form in which rubidium is usually sold. Preparation This salt can be prepared by adding ammonium carbonate to rubidium hydroxide Rubidium hydroxide is the inorganic compound with the formula RbOH. It consists of rubidium cations and an equal number of hydroxide anions. It is a colorless solid that is commercially available as aqueous solutions from a few suppliers. Like ot .... Uses It is used in some kinds of glass-making by enhancing stability and durability as well as reducing its conductivity. It is also used as a part of a catalyst for preparing short-chain alcohols from feed gas. References Carbonates Rubidium compounds {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrobromic Acid
Hydrobromic acid is a strong acid formed by dissolving the diatomic molecule hydrogen bromide (HBr) in water. "Constant boiling" hydrobromic acid is an aqueous solution that distills at and contains 47.6% HBr by mass, which is 8.77 mol/L. Hydrobromic acid has a p''K''a of −9, making it a stronger acid than hydrochloric acid, but not as strong as hydroiodic acid. Hydrobromic acid is one of the strongest mineral acids known. Uses Hydrobromic acid is mainly used for the production of inorganic bromides, especially the bromides of zinc, calcium, and sodium. It is a useful reagent for generating organobromine compounds. Certain ethers are cleaved with HBr. It also catalyzes alkylation reactions and the extraction of certain ores. Industrially significant organic compounds prepared from hydrobromic acid include allyl bromide, tetrabromobis(phenol), and bromoacetic acid. HBr almost uniquely participates in anti-Markovnikov hydrohalogenation of alkenes. The resulting 1-bro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Hydroxide
Rubidium hydroxide is the inorganic compound with the formula RbOH. It consists of rubidium cations and an equal number of hydroxide anions. It is a colorless solid that is commercially available as aqueous solutions from a few suppliers. Like other strong bases, rubidium hydroxide is highly corrosive. Rubidium hydroxide is formed when rubidium metal reacts with water. Uses Rubidium hydroxide is rarely used in industrial processes because potassium hydroxide and sodium hydroxide can perform nearly all the same functions of rubidium hydroxide. Metal oxide catalysts are sometimes modified with rubidium hydroxide. See also *Potassium hydroxide *Sodium hydroxide *Rubidium Rubidium is the chemical element with the symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher ... References * * {{DEFAULTSORT:Rubidium Hydroxide Rubi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Chloride
Sodium chloride , commonly known as salt (although sea salt also contains other chemical salts), is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. With molar masses of 22.99 and 35.45 g/mol respectively, 100 g of NaCl contains 39.34 g Na and 60.66 g Cl. Sodium chloride is the salt most responsible for the salinity of seawater and of the extracellular fluid of many multicellular organisms. In its edible form, salt (also known as ''table salt'') is commonly used as a condiment and food preservative. Large quantities of sodium chloride are used in many industrial processes, and it is a major source of sodium and chlorine compounds used as feedstocks for further chemical syntheses. Another major application of sodium chloride is de-icing of roadways in sub-freezing weather. Uses In addition to the familiar domestic uses of salt, more dominant applications of the approximately 250 million tonnes per year production (2008 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromide
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 react ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Chloride
Rubidium chloride is the chemical compound with the formula RbCl. This alkali metal halide salt is composed of rubidium and chlorine, and finds diverse uses ranging from electrochemistry to molecular biology. Structure In its gas phase, RbCl is diatomic with a bond length estimated at 2.7868 Å. This distance increases to 3.285 Å for cubic RbCl, reflecting the higher coordination number of the ions in the solid phase. Depending on conditions, solid RbCl exists in one of three arrangements or polymorphs as determined with holographic imaging: Sodium chloride (octahedral 6:6) The sodium chloride (NaCl) polymorph is most common. A cubic close-packed arrangement of chloride anions with rubidium cations filling the octahedral holes describes this polymorph. Both ions are six-coordinate in this arrangement. The lattice energy of this polymorph is only 3.2 kJ/mol less than the following structure's. Caesium chloride (cubic 8:8) At high temperature and pressure, RbCl a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Francium Bromide
Francium is a chemical element with the symbol Fr and atomic number 87. It is extremely radioactive; its most stable isotope, francium-223 (originally called actinium K after the natural decay chain it appears in), has a half-life of only 22 minutes. It is the second-most electropositive element, behind only caesium, and is the second rarest naturally occurring element (after astatine). The isotopes of francium decay quickly into astatine, radium, and radon. The electronic structure of a francium atom is n7s1, and so the element is classed as an alkali metal. Bulk francium has never been seen. Because of the general appearance of the other elements in its periodic table column, it is presumed that francium would appear as a highly reactive metal, if enough could be collected together to be viewed as a bulk solid or liquid. Obtaining such a sample is highly improbable, since the extreme heat of decay resulting from its short half-life would immediately vaporize any viewabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
