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Calcium Phosphide
Calcium phosphide (CP) is the inorganic compound with the formula Ca3P2. It is one of several phosphides of calcium, being described as the salt-like material composed of Ca2+ and P3−. Other, more exotic calcium phosphides have the formula CaP / Ca2P2, CaP3, and Ca5P8. Ca3P2 has the appearance of red-brown crystalline powder or grey lumps. Its trade name is Photophor for the incendiary use or Polytanol for the use as rodenticide. Preparation, history and structure It may be formed by reaction of the elements, but it is more commonly prepared by carbothermal reduction of calcium phosphate: :Ca3(PO4)2 + 8 C → Ca3P2 + 8 CO This is also the way how it was accidentally discovered by Smithson Tennant in 1791 while verifying the composition of carbon dioxide proposed by Antoine Lavoisier by reducing calcium carbonate with phosphorus. The structure of the room temperature form of Ca3P2 has not been confirmed by X-ray crystallography. A high temperature phase h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphine
Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula , classed as a pnictogen hydride. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting fish, due to the presence of substituted phosphine and diphosphane (). With traces of present, is spontaneously flammable in air ( pyrophoric), burning with a luminous flame. Phosphine is a highly toxic respiratory poison, and is immediately dangerous to life or health at 50 ppm. Phosphine has a trigonal pyramidal structure. Phosphines are compounds that include and the organophosphines, which are derived from by substituting one or more hydrogen atoms with organic groups. They have the general formula . Phosphanes are saturated phosphorus hydrides of the form , such as triphosphane. Phosphine () is the smallest of the phosphines and the smallest of the phosphanes. History Philippe Gengembre (1764–1838), a student of Lavoisi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Phosphide
Zinc phosphide ( Zn3 P2) is an inorganic chemical compound. It is a grey solid, although commercial samples are often dark or even black. It is used as a rodenticide. Zn3P2 is a II-V semiconductor with a direct band gap of 1.5 eV and may have applications in photovoltaic cells. A second compound exists in the zinc-phosphorus system, zinc diphosphide (ZnP2). Synthesis and reactions Zinc phosphide can be prepared by the reaction of zinc with phosphorus; however, for critical applications, additional processing to remove arsenic compounds may be needed. :6 Zn + P4 → 2 Zn3P2 Another method of preparation include reacting tri-n-octylphosphine with dimethylzinc. Zinc phosphide reacts with water to produce highly toxic phosphine (PH3) and zinc hydroxide (Zn(OH)2): :Zn3P2 + 6 H2O → 2 PH3 + 3 Zn(OH)2 Structure Zn3P2 has a room-temperature tetragonal form that converts to a cubic form at around 845 °C.Evgeniĭ I︠U︡rʹevich Tonkov, 1992, High Pressure Pha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Compounds
Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and the third most abundant metal, after iron and aluminium. The most common calcium compound on Earth is calcium carbonate, found in limestone and the fossils of early sea life; gypsum, anhydrite, fluorite, and apatite are also sources of calcium. The name comes from Latin ''calx'' " lime", which was obtained from heating limestone. Some calcium compounds were known to the ancients, though their chemistry was unknown until the seventeenth century. Pure calcium was isolated in 1808 via electrolysis of its oxide by Humphry Davy, who named the element. Calcium compounds are widely used in many industries: in foods and pharmaceuticals for calc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphides
In chemistry, a phosphide is a compound containing the ion or its equivalent. Many different phosphides are known, with widely differing structures. Most commonly encountered on the binary phosphides, i.e. those materials consisting only of phosphorus and a less electronegative element. Numerous are polyphosphides, which are solids consisting of anionic chains or clusters of phosphorus. Phosphides are known with the majority of less electronegative elements with the exception of Hg, Pb, Sb, Bi, Te, and Po.Von Schnering, H.G. and Hönle , W. (1994) "Phosphides - Solid-state Chemistry" in ''Encyclopedia of Inorganic Chemistry''. R. Bruce King (ed.). John Wiley & Sons Finally, some phosphides are molecular. Binary phosphides Binary phosphides include phosphorus and one other element. An example of a group 1 phosphide is sodium phosphide (). Other notable examples include aluminium phosphide () and calcium phosphide (), which are used as pesticides, exploiting their tend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus
Phosphorus is a chemical element; it has Chemical symbol, symbol P and atomic number 15. All elemental forms of phosphorus are highly Reactivity (chemistry), reactive and are therefore never found in nature. They can nevertheless be prepared artificially, the two most common allotropes being white phosphorus and red phosphorus. With as its only stable isotope, phosphorus has an occurrence in Earth's crust of about 0.1%, generally as phosphate rock. A member of the pnictogen family, phosphorus readily forms a wide variety of organic compound, organic and inorganic compound, inorganic compounds, with as its main oxidation states +5, +3 and −3. The isolation of white phosphorus in 1669 by Hennig Brand marked the scientific community's first discovery since Antiquity of an element. The name phosphorus is a reference to the Phosphorus (morning star), god of the Morning star in Greek mythology, inspired by the faint glow of white phosphorus when exposed to oxygen. This property is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylene
Acetylene (Chemical nomenclature, systematic name: ethyne) is a chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in its pure form and thus is usually handled as a solution. Pure acetylene is odorless, but commercial grades usually have a marked odor due to impurities such as divinyl sulfide and phosphine.Compressed Gas Association (1995Material Safety and Data Sheet – Acetylene As an alkyne, acetylene is Saturated and unsaturated compounds, unsaturated because its two carbon atoms are Chemical bond, bonded together in a triple bond. The carbon–carbon triple bond places all four atoms in the same straight line, with CCH bond angles of 180°. The triple bond in acetylene results in a high energy content that is released when acetylene is burned. Discovery Acetylene was discovered in 1836 by Edmund Davy, who identified it as a "new carburet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colin McEvedy
Colin Peter McEvedy (6 June 1930 – 1 August 2005) was a British polymath scholar, psychiatrist, historian, demographer and non-fiction author. Early life Colin Peter McEvedy was born in Salford, Lancashire on 6 June 1930. He was the third son of Peter George McEvedy, a renowned surgeon, who was born in New Zealand. Colin was educated at Harrow School, where he was a scholar, and Magdalen College, Oxford. Career McEvedy's profession was psychiatry, in which he had a distinguished career. He became perhaps better known, though, as a historian and demographer, and certainly so by the public at large. Between 1961 and 2002 he produced a number of historical atlases which, unlike most such atlases, feature fixed base-maps; in most cases, each atlas uses a single principal base-map, which is shown repeatedly, at many dates, as the atlas goes along, thus illustrating changes over the ages, from ancient down to modern, within the chosen area. The accompanying text, typically, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Fire
Greek fire was an incendiary weapon system used by the Byzantine Empire from the seventh to the fourteenth centuries. The recipe for Greek fire was a closely-guarded state secret; historians have variously speculated that it was based on saltpeter, sulfur, or quicklime, but most modern scholars agree that it was based on petroleum mixed with resins, comparable in composition to modern napalm. Byzantine sailors would toss grenades loaded with Greek fire onto enemy ships or spray it from tubes. Its ability to burn on water made it an effective and destructive naval incendiary weapon, and rival powers tried unsuccessfully to copy the material. Name Usage of the term "Greek fire" has been general in English and most other languages since the Crusades. Original Byzantine sources called the substance a variety of names, such as "sea fire" (Medieval Greek: ), "Roman fire" ( ), "war fire" ( ), "liquid fire" ( ), "sticky fire" ( ), or "manufactured fire" ( ). History Incendiary and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Carbide
Calcium carbide, also known as calcium acetylide, is a chemical compound with the chemical formula of . Its main use industrially is in the production of acetylene and calcium cyanamide. The pure material is colorless, while pieces of technical-grade calcium carbide are grey or brown and consist of about 80–85% of (the rest is CaO ( calcium oxide), ( calcium phosphide), CaS ( calcium sulfide), ( calcium nitride), SiC (silicon carbide), C (carbon), etc.). In the presence of trace moisture, technical-grade calcium carbide emits an unpleasant odor reminiscent of garlic. Applications of calcium carbide include manufacture of acetylene gas, generation of acetylene in carbide lamps, manufacture of chemicals for fertilizer, and steelmaking. Production Calcium carbide is produced industrially in an electric arc furnace from a mixture of lime and coke at approximately . This is an endothermic reaction requiring per mole and high temperatures to drive off the carbon monoxide. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Kingsford Smith
Sir Charles Edward Kingsford Smith (9 February 18978 November 1935), nicknamed Smithy, was an Australian aviation pioneer. He piloted the first transpacific flight and the first flight between Australia and New Zealand. Kingsford Smith was born in Brisbane. He grew up in Sydney, leaving school at the age of 16 and becoming an engineering apprentice. He joined the Australian Army in 1915 and was a motorcycle despatch rider on the Gallipoli campaign. He later transferred to the Royal Flying Corps and was awarded the Military Cross in 1917 after being shot down. After the war's end, Kingsford Smith worked as a Barnstorming, barnstormer in England and the United States before returning to Australia in 1921. He subsequently joined West Australian Airways as one of the country's first commercial pilots. In 1928, Kingsford Smith completed the first transpacific flight, a three-leg journey from California to Brisbane via Hawaii and Fiji. He and his co-pilot Charles Ulm became celebr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrotechnic Flare
A flare, also sometimes called a fusée, fusee, or bengala, bengalo in several European countries, is a type of pyrotechnic that produces a bright light or intense heat without an explosion. Flares are used for distress signaling, illumination, or defensive countermeasures in civilian and military applications. Flares may be ground pyrotechnics, projectile pyrotechnics, or parachute-suspended to provide maximum illumination time over a large area. Projectile pyrotechnics may be dropped from aircraft, fired from rocket or artillery, or deployed by flare guns or handheld percussive tubes. Origin The earliest recorded use of gunpowder for signaling purposes was the 'signal bomb' used by the Chinese Song Dynasty (960–1279) as the Mongol-led Yuan Dynasty (1271–1368) besieged Yangzhou in 1276. These soft-shelled bombs, timed to explode in midair, were used to send messages to a detachment of troops far in the distance. Another mention of the signal bomb appears in a text datin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such a device was called an automotive, automobile, locomotive, or fish torpedo; colloquially, a ''fish''. The term ''torpedo'' originally applied to a variety of devices, most of which would today be called mines. From about 1900, ''torpedo'' has been used strictly to designate a self-propelled underwater explosive device. While the 19th-century battleship had evolved primarily with a view to engagements between armored warships with large-caliber guns, the invention and refinement of torpedoes from the 1860s onwards allowed small torpedo boats and other lighter surface vessels, submarines/submersibles, even improvised fishing boats or frogmen, and later light aircraft, to destroy large ships without the need of large guns, though somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
