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Promethium Hydroxide
Promethium(III) hydroxide is an inorganic compound with a chemical formula Pm(OH)3. It is a radioactive Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is conside ... compound. Production Promethium(III) hydroxide can be produced by reacting ammonia water with a solution of a promethium(III) salt, from which promethium(III) hydroxide precipitates as a purplish-pink amorphous solid. By heating with water, it can be forced to crystallize, giving hexagonal crystals isomorphous with other rare earth hydroxides: : Pm3+ + 3OH− → Pm(OH)3↓ References {{hydroxides Promethium compounds Hydroxides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promethium Oxide
Promethium(III) oxide is a compound with the formula Pm2O3. It is the most common form of promethium Promethium is a chemical element; it has Symbol (chemistry), symbol Pm and atomic number 61. All of its isotopes are Radioactive decay, radioactive; it is extremely rare, with only about 500–600 grams naturally occurring in the Earth's crust a .... 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] |
Neodymium(III) Hydroxide
Neodymium(III) hydroxide is an insoluble inorganic compound with the chemical formula Nd(OH)3. Preparation Neodymium(III) nitrate and ammonia water will react to produce neodymium(III) hydroxide:《无机化合物制备手册》. 朱文祥 主编. 化学工业出版社. 【III-119】氢氧化钕（neodymium hydroxide） : Nd(NO3)3 + 3 NH3·H2O → Nd(OH)3↓ + 3 NH4NO3 If the amount of Nd(NO3)3 is 40g/L, the amount of ammonia water needed is 0.50 mol/L. The ammonia water is mixed into the Nd(NO3)3 solution at the speed of 1.5mL/min, and polyethylene glycol is used to control pH. The process will produce neodymium(III) hydroxide powder with grain size ≤1μm. Chemical properties Neodymium(III) hydroxide can react with acid and produce neodymium salts: : Nd(OH)3 + 3 H+ → Nd3+ + 3 H2O For example, to create neodymium acetate with neodymium(III) hydroxide: :Nd(OH)3 + 3CH3COOH → Nd(CH3COO)3 + 3H2O See also * Neodymium * Hydroxide * Lanthanide The lanthanide () or lant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samarium(III) Hydroxide
Samarium(III) hydroxide is an inorganic compound with chemical formula Sm(OH)3. Chemical properties Samarium(III) hydroxide can react with acid An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis ... 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 Hydroxides Samarium(III) compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radioactive
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered ''radioactive''. Three of the most common types of decay are Alpha decay, alpha, Beta decay, beta, and Gamma ray, gamma decay. The weak force is the Fundamental interactions, mechanism that is responsible for beta decay, while the other two are governed by the electromagnetic force, electromagnetic and nuclear forces. Radioactive decay is a randomness, random process at the level of single atoms. According to quantum mechanics, quantum theory, it is impossible to predict when a particular atom will decay, regardless of how long the atom has existed. However, for a significant number of identical atoms, the overall decay rate can be expressed as a decay constant or as a half-life. The half-lives of radioactive atoms have a huge range: f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonia Solution
Ammonia solution, also known as ammonia water, ammonium hydroxide, ammoniacal liquor, ammonia liquor, aqua ammonia, aqueous ammonia, or (inaccurately) ammonia, is a solution of ammonia in water. It can be denoted by the symbols NH3(aq). Although the name ammonium hydroxide suggests a salt with the composition , it is impossible to isolate samples of NH4OH. The ions and OH− do not account for a significant fraction of the total amount of ammonia except in extremely dilute solutions. The concentration of such solutions is measured in units of the Baumé scale (density), with 26 degrees Baumé (about 30% of ammonia by weight at ) being the typical high-concentration commercial product. Basicity of ammonia in water In aqueous solution, ammonia deprotonates a small fraction of the water to give ammonium and hydroxide according to the following equilibrium: : NH3 + H2O ⇌ + OH−. In a 1 M ammonia solution, about 0.42% of the ammonia is converted to ammonium, equivalent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promethium Compounds
Promethium compounds are compounds containing the element promethium, which normally take the +3 oxidation state. Promethium belongs to the cerium group of lanthanides and is chemically very similar to the neighboring elements. Because of its instability, chemical studies of promethium are incomplete. Even though a few compounds have been synthesized, they are not fully studied; in general, they tend to be pink or red in color.promethium Encyclopædia Britannica Online Treatment of acidic solutions containing Pm3+ ions with results in a gelatinous light-brown sediment of hydroxide, Pm(OH)3, which is insoluble in water. When dissolved in |
