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Americium Compounds
Americium compounds are compounds containing the element americium (Am). These compounds can form in the +2, +3, and +4, although the +3 oxidation state is the most common. The +5, +6 and +7 oxidation states have also been reported. Oxides Three americium oxides are known, with the oxidation states +2 (AmO), +3 (), and +4 (). Americium(II) oxide was prepared in minute amounts and has not been characterized in detail. Americium(III) oxide is a red-brown solid with a melting point of 2205 °C.Wiberg, p. 1972 Americium dioxide, Americium(IV) oxide is the main form of solid americium which is used in nearly all its applications. Like most other actinide dioxides, it is a black solid with a cubic (fluorite) crystal structure.Greenwood, p. 1267 The oxalate of americium(III), vacuum dried at room temperature, has the chemical formula . Upon heating in vacuum, it loses water at 240 °C and starts decomposing into at 300 °C, the decomposition completes at about 470 °C. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Americium
Americium is a synthetic element, synthetic chemical element; it has Chemical symbol, symbol Am and atomic number 95. It is radioactive and a transuranic member of the actinide series in the periodic table, located under the lanthanide element europium and was thus named after the Americas by analogy. Americium was first produced in 1944 by the group of Glenn T. Seaborg from Berkeley, California, at the Metallurgical Laboratory of the University of Chicago, as part of the Manhattan Project. Although it is the third element in the transuranic series, it was discovered fourth, after the heavier curium. The discovery was kept secret and only released to the public in November 1945. Most americium is produced by uranium or plutonium being bombarded with neutrons in nuclear reactors – one tonne of spent nuclear fuel contains about 100 grams of americium. It is widely used in commercial ionization chamber smoke detectors, as well as in neutron sources and industrial gauges. Several u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetragonal Crystal System
In crystallography, the tetragonal crystal system is one of the 7 crystal systems. Tetragonal crystal lattices result from stretching a cubic lattice along one of its lattice vectors, so that the cube becomes a rectangular prism with a square base (''a'' by ''a'') and height (''c'', which is different from ''a''). Bravais lattices There are two tetragonal Bravais lattices: the primitive tetragonal and the body-centered tetragonal. The body-centered tetragonal lattice is equivalent to the primitive tetragonal lattice with a smaller unit cell, while the face-centered tetragonal lattice is equivalent to the body-centered tetragonal lattice with a smaller unit cell. Crystal classes The point groups that fall under this crystal system are listed below, followed by their representations in international notation, Schoenflies notation, orbifold notation, Coxeter notation and mineral examples.Hurlbut, Cornelius S.; Klein, Cornelis, 1985, ''Manual of Mineralogy'', 20th ed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Carbonate
Potassium carbonate is the inorganic compound with the formula . It is a white salt, which is soluble in water and forms a strongly alkaline solution. It is deliquescent, often appearing as a damp or wet solid. Potassium carbonate is mainly used in the production of soap and glass. Commonly, it can be found as the result of leakage of alkaline batteries. Potassium carbonate is a potassium salt of carbonic acid. This salt consists of potassium cations and carbonate anions , and is therefore an alkali metal carbonate. History Potassium carbonate is the primary component of potash and the more refined pearl ash or salt of tartar. Historically, pearl ash was created by baking potash in a kiln to remove impurities. The fine, white powder remaining was the pearl ash. The first patent issued by the US Patent Office was awarded to Samuel Hopkins in 1790 for an improved method of making potash and pearl ash. In late 18th-century North America, before the development of baking pow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexagonal Crystal Family
In crystallography, the hexagonal crystal family is one of the six 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 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 rhombohedral. Each lattice system consists of one Bravais ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Bicarbonate
Potassium bicarbonate ( IUPAC name: potassium hydrogencarbonate, also known as potassium acid carbonate) is the inorganic compound with the chemical formula KHCO3. It is a white solid. Production and reactivity It is manufactured by treating an aqueous solution of potassium carbonate or potassium hydroxide with carbon dioxide: :K2CO3 + CO2 + H2O → 2 KHCO3 Decomposition of the bicarbonate occurs between : :2 KHCO3 → K2CO3 + CO2 + H2O This reaction is employed to prepare high purity potassium carbonate. Uses Food and drink This compound is a source of carbon dioxide for leavening in baking. It can substitute for baking soda (sodium bicarbonate) for those with a low-sodium diet, and it is an ingredient in low-sodium baking powders. As an inexpensive, nontoxic base, it is widely used in diverse application to regulate pH or as a reagent. Examples include as buffering agent in medications, an additive in winemaking. Potassium bicarbonate is often added to bottled water to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slurry
A slurry is a mixture of denser solids suspended in liquid, usually water. The most common use of slurry is as a means of transporting solids or separating minerals, the liquid being a carrier that is pumped on a device such as a centrifugal pump. The size of solid particles may vary from 1 micrometre up to hundreds of millimetres. The particles may settle below a certain transport velocity and the mixture can behave like a Newtonian or non-Newtonian fluid. Depending on the mixture, the slurry may be abrasive and/or corrosive. Examples Examples of slurries include: *Cement slurry, a mixture of cement, water, and assorted dry and liquid additives used in the petroleum and other industries *Soil/cement slurry, also called Controlled Low-Strength Material (CLSM), flowable fill, controlled density fill, flowable mortar, plastic soil-cement, K-Krete, and other names *A mixture of thickening agent, oxidizers, and water used to form a gel explosive *A mixture of pyroclastic materi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozone
Ozone () (or trioxygen) is an Inorganic compound, inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the lower atmosphere to (dioxygen). Ozone is formed from dioxygen by the action of ultraviolet (UV) light and electrical discharges within the Earth's atmosphere. It is present in very low concentrations throughout the atmosphere, with its highest concentration high in the ozone layer of the stratosphere, which absorbs most of the Sun's ultraviolet (UV) radiation. Ozone's odor is reminiscent of chlorine, and detectable by many people at concentrations of as little as in air. Ozone's O3 chemical structure, structure was determined in 1865. The molecule was later proven to have a bent structure and to be weakly diamagnetism, diamagnetic. At standard temperature and pressure, ozone is a pale blue gas that condenses at cryogenic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manhattan Project
The Manhattan Project was a research and development program undertaken during World War II to produce the first nuclear weapons. It was led by the United States in collaboration with the United Kingdom and Canada. From 1942 to 1946, the project was directed by Major General Leslie Groves of the United States Army Corps of Engineers, U.S. Army Corps of Engineers. Nuclear physicist J. Robert Oppenheimer was the director of the Los Alamos Laboratory that designed the bombs. The Army program was designated the Manhattan District, as its first headquarters were in Manhattan; the name gradually superseded the official codename, Development of Substitute Materials, for the entire project. The project absorbed its earlier British counterpart, Tube Alloys, and subsumed the program from the American civilian Office of Scientific Research and Development. The Manhattan Project employed nearly 130,000 people at its peak and cost nearly US$2 billion (equivalent to about $ b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Americium(III) Hydroxide
Americium(III) hydroxide is a radioactive inorganic compound with the chemical formula . It consists of one americium atom and three hydroxy groups. It was first discovered in 1944, closely related to the Manhattan Project. However, these results were confidential and were only released to the public in 1945. It was the first isolated sample of an americium compound, and the first americium compound discovered. Properties Americium hydroxide is a pink solid which is sparingly soluble in water. Due to self-irradiation, the crystal structure of decomposes within 4 to 6 months ( has a half-life of 432.2 years); for the same process takes one day ( has a half-life of 18.11 years). Synthesis Americium metal can be converted to in a four-step process. As described by the Oak Ridge National Laboratory, americium is added to hydrochloric acid, then neutralized using ammonium hydroxide (). A saturated oxalic acid solution is added to the now neutralized solution. This causes large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of Biomolecule, biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclinic Crystal System
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic system. They form a parallelogram prism. Hence two pairs of vectors are perpendicular (meet at right angles), while the third pair makes an angle other than 90°. Bravais lattices Two monoclinic Bravais lattices exist: the primitive monoclinic and the base-centered monoclinic. For the base-centered monoclinic lattice, the primitive cell has the shape of an oblique rhombic prism;See , row mC, column Primitive, where the cell parameters are given as a1 = a2, α = β it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. The length a of the primitive cell below equals \frac \sqrt of the conventional cell above. Crystal classes The table below organizes the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrochloric Acid
Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is a component of the gastric acid in the digestive systems of most animal species, including humans. Hydrochloric acid is an important laboratory reagent and industrial chemical. Etymology Because it was produced from halite, rock salt according to the methods of Johann Rudolph Glauber, hydrochloric acid was historically called by European alchemists ''spirits of salt'' or ''acidum salis'' (salt acid). Both names are still used, especially in other languages, such as , , , , , , , , , , (''ensan''), zh, 盐酸 (''yánsuān''), and (''yeomsan''). Gaseous HCl was called ''marine acid air''. The name ''muriatic acid'' has the same origin (''muriatic'' means "pertaining to brine or salt", hence ''muriate'' means hydrochloride), and this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
