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Samarium(III) Nitrate
Samarium(III) nitrate is an odorless, white-colored chemical compound with the formula Sm(NO3)3. It forms the hexahydrate, which decomposes at 50°C to the anhydrous form. When further heated to 420°C, it is converted to the oxynitrate, and at 680°C it decomposes to form samarium(III) oxide. Synthesis Samarium(III) nitrate is produced by the reaction of samarium hydroxide and nitric acid: : Uses Samarium(III) nitrate is a lewis acid catalyst that is used to produce a nitrate precursor solution that is used as a nanocatalyst in the solid oxide regenerative fuel cells. The nanocatalyst is made by mixing samarium(III) nitrate hexahydrate, strontium nitrate, and cobalt(II) nitrate hexahydrate. Samarium(III) nitrate is also used for the preparation of samarium doped ceria, which can be used in the fabrication of electrolytes for fuel cells. The samarium doped ceria is produced by mixing cerium(III) nitrate Cerium nitrate refers to a family of nitrates of cerium in the +3 or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samarium(III) Oxide
Samarium(III) oxide ( Sm2 O3) is a chemical compound. Samarium oxide readily forms on the surface of samarium metal under humid conditions or temperatures in excess of 150°C in dry air. Similar to rust on metallic iron, this oxide layer spalls off the surface of the metal, exposing more metal to continue the reaction. The oxide is commonly white to off yellow in color and is often encountered as a highly fine dust like powder. Uses Samarium(III) oxide is used in optical and infrared absorbing glass to absorb infrared radiation. Also, it is used as a neutron absorber in control rods for nuclear power reactors. The oxide catalyzes the dehydration and dehydrogenation of primary and secondary alcohols. Another use involves preparation of other samarium salts. Pradyot Patnaik. ''Handbook of Inorganic Chemicals''. McGraw-Hill, 2002, Preparations Samarium(III) oxide may be prepared by two methods: 1. thermal decomposition of samarium(III) carbonate, hydroxide, nitrate, oxalate or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samarium Hydroxide
Samarium(III) hydroxide is an inorganic compound with chemical formula Sm(OH)3. Chemical properties Samarium(III) hydroxide can react with acid In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ... and produce samarium salts： : Sm(OH)3 + 3 H+ → Sm3+ + 3 H2O Samarium(III) hydroxide will decompose to SmO(OH) when heated; continued heating produces Sm2O3. References {{hydroxides Samarium compounds Hydroxides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Acid
Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitric acid has a concentration of 68% in water. When the solution contains more than 86% , it is referred to as ''fuming nitric acid''. Depending on the amount of nitrogen dioxide present, fuming nitric acid is further characterized as red fuming nitric acid at concentrations above 86%, or white fuming nitric acid at concentrations above 95%. Nitric acid is the primary reagent used for nitration – the addition of a nitro group, typically to an organic molecule. While some resulting nitro compounds are shock- and thermally-sensitive explosives, a few are stable enough to be used in munitions and demolition, while others are still more stable and used as pigments in inks and dyes. Nitric acid is also commonly used as a strong oxidizing agen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lewis Acid
A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any species that has a filled orbital containing an electron pair which is not involved in bonding but may form a dative bond with a Lewis acid to form a Lewis adduct. For example, NH3 is a Lewis base, because it can donate its lone pair of electrons. Trimethylborane (Me3B) is a Lewis acid as it is capable of accepting a lone pair. In a Lewis adduct, the Lewis acid and base share an electron pair furnished by the Lewis base, forming a dative bond. In the context of a specific chemical reaction between NH3 and Me3B, a lone pair from NH3 will form a dative bond with the empty orbital of Me3B to form an adduct NH3•BMe3. The terminology refers to the contributions of Gilbert N. Lewis. From p. 142: "We are inclined to think of substances as po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalyst
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid Oxide Fuel Cell
A solid oxide fuel cell (or SOFC) is an electrochemical conversion device that produces electricity directly from oxidizing a fuel. Fuel cells are characterized by their electrolyte material; the SOFC has a solid oxide or ceramic electrolyte. Advantages of this class of fuel cells include high combined heat and power efficiency, long-term stability, fuel flexibility, low emissions, and relatively low cost. The largest disadvantage is the high operating temperature which results in longer start-up times and mechanical and chemical compatibility issues. Introduction Solid oxide fuel cells are a class of fuel cells characterized by the use of a solid oxide material as the electrolyte. SOFCs use a solid oxide electrolyte to conduct negative oxygen ions from the cathode to the anode. The electrochemical oxidation of the hydrogen, carbon monoxide or other organic intermediates by oxygen ions thus occurs on the anode side. More recently, proton-conducting SOFCs (PC-SOFC) are being deve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strontium Nitrate
Strontium nitrate is an inorganic compound composed of the elements strontium, nitrogen and oxygen with the formula Sr( NO3)2. This colorless solid is used as a red colorant and oxidizer in pyrotechnics. Preparation Strontium nitrate is typically generated by the reaction of nitric acid on strontium carbonate. : 2 HNO3 + SrCO3 → Sr(NO3)2 + H2O + CO2 Uses Like many other strontium salts, strontium nitrate is used to produce a rich red flame in fireworks and road flares. The oxidizing properties of this salt are advantageous in such applications.MacMillan, J. Paul; Park, Jai Won; Gerstenberg, Rolf; Wagner, Heinz; Köhler, Karl and Wallbrecht, Peter (2002) "Strontium and Strontium Compounds" in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim. Strontium nitrate can aid in eliminating and lessening skin irritations. When mixed with glycolic acid, strontium nitrate reduces the sensation of skin irritation significantly better than using glycolic ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobalt(II) Nitrate
Cobalt is a chemical element with the symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal. Cobalt-based blue pigments (cobalt blue) have been used since ancient times for jewelry and paints, and to impart a distinctive blue tint to glass, but the color was for a long time thought to be due to the known metal bismuth. Miners had long used the name ''kobold ore'' (German for ''goblin ore'') for some of the blue-pigment-producing minerals; they were so named because they were poor in known metals, and gave poisonous arsenic-containing fumes when smelted. In 1735, such ores were found to be reducible to a new metal (the first discovered since ancient times), and this was ultimately named for the ''kobold''. Today, some cobalt is produced specifically from one of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceria
Cerium(IV) oxide, also known as ceric oxide, ceric dioxide, ceria, cerium oxide or cerium dioxide, is an oxide of the rare-earth metal cerium. It is a pale yellow-white powder with the chemical formula CeO2. It is an important commercial product and an intermediate in the purification of the element from the ores. The distinctive property of this material is its reversible conversion to a non-stoichiometric oxide. Production Cerium occurs naturally as oxides, always as a mixture with other rare-earth elements. Its principal ores bastnaesite and monazite. After extraction of the metal ions into aqueous base, Ce is separated from that mixture by addition of an oxidant followed by adjustment of the pH. This step exploits the low solubility of CeO2 and the fact that other rare-earth elements resist oxidation.. Cerium(IV) oxide is formed by the calcination of cerium oxalate or cerium hydroxide. Cerium also forms cerium(III) oxide, , which is unstable and will oxidize to ceriu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerium(III) Nitrate
Cerium nitrate refers to a family of nitrates of cerium in the +3 or +4 oxidation state. Often these compounds contain water, hydroxide, or hydronium ions in addition to cerium and nitrate. Double nitrates of cerium also exist. Cerium(III) nitrates Anhydrous cerous nitrate, also called cerium(III) nitrate, is the anhydrous salt with the formula Ce(NO3)3.(CAS number 10108-73-3). Cerium nitrate hexahydrate, with the formula Ce(NO3)3.6H2O (CAS number 10294-41-4) is the most common nitrate of cerium(III). It is a component in a burn treatment cream that also includes silver sulphadiazine. Concentrations used are 0.5 M for the cerium nitrate. For very serious burns it reduces the death rate. At 150 °C the hexahydrate loses water of crystallization to make a trihydrate, which itself decomposes above 200 °C. Cerous nitrate hexahydrate has pinacoidal triclinic crystals. Hydronium cerium(III) nitrate hydrate, Ce(NO3)5(H3O)2.H2O It is monoclinic with space group ''P''2/''c''. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triethylene Glycol
Triethylene glycol, TEG, or triglycol is a colorless odorless viscous liquid with molecular formula HOCH2CH2OCH2CH2OCH2CH2OH. It is used as a plasticizer for vinyl polymers. It is also used in air sanitizer products, such as "Oust" or "Clean and Pure". When aerosolized it acts as a disinfectant. Glycols are also used as liquid desiccants for natural gas and in air conditioning systems. It is an additive for hydraulic fluids and brake fluids and is used as a base for " smoke machine" fluid in the entertainment industry. Properties Triethylene glycol is a member of a homologous series of dihydroxy alcohols. It is a colorless, odorless and stable liquid with high viscosity and a high boiling point. Apart from its use as a raw material in the manufacture and synthesis of other products, TEG is known for its hygroscopic quality and its ability to dehumidify fluids. This liquid is miscible with water, and at standard atmospheric pressure (101.325 kPa) has a boiling point of 286.5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrates
Nitrate is a polyatomic ion with the chemical formula . Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are soluble in water. An example of an insoluble nitrate is bismuth oxynitrate. Structure The ion is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a formal charge of −1. This charge results from a combination formal charge in which each of the three oxygens carries a − charge, whereas the nitrogen carries a +1 charge, all these adding up to formal charge of the polyatomic nitrate ion. This arrangement is commonly used as an example of resonance. Like the isoelectronic carbonate ion, the nitrate ion can be represented by resonance structures: Dietary nitrate A rich source of inorganic nitrate in the human diets come from leafy green foods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
