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Tungsten Complete Name of the Element: Tungsten How Name Was Derived: Nordic meaning “Heavy stone” Symbol of the meaning: W Atomic # of the Element: 74 Atomic Mass of the Element: 183.84 Natural State of the Element: Solid Structure of the Element: 74 Protons, 110 Neutrons Chemical Properties: Tungsten has a melting point of 3410+/-20°C, boiling point of 5660°C, specific gravity of 19.3 (20°C), with a valence of 2, 3, 4, 5, or 6. Tungsten is a steel-gray to tin-white metal. Impure tungsten metal is quite brittle, although pure tungsten can be cut with a saw, spun, drawn, forged, and extruded. Tungsten has the highest melting point and the lowest vapor pressure of the metals. At temperatures exceeding 1650°C, it has the highest tensile strength. Tungsten oxidizes in air at elevated temperatures, although it generally has excellent corrosion resistance and is minimally attacked by most acids. Occurrence The more important tungsten ores are wolframite and scheelite; with smaller importance can also be considered tungstite and cuprotungstite. The largest world deposits occur in China (75% of the total), and in smaller amounts in other countries such as Portugal. The most important extraction mines in Portugal are located in Panasqueira and in Borralha, from which, during II World War, about 6000 tons of ores per year were extracted. Uses of Tungsten Approximately half of the tungsten mined is used to create tungsten carbine. This makes other materials harder. Tungsten Carbine is used to make wear-resistant abrasives, cutters and knives. Items such as drill bits, circular saws, metal work tools and woodwork tools, It is used in mining drills as it has a high melting point and is extremely hardy. Almost 60% of tungsten is used in this industry, It is used to make rings in the jewelry industry. This is due to its scratch resistant qualities. Tungsten is commonly used to make hard metal alloys such as high speed steel. Metals alloys with tungsten are often used to make turbine blades, rocket nozzles and metal coatings, It is also used in the creation of armor piercing bullets, cannon shells, grenades and missiles to create supersonic shrapnel, It has also been used to create Dense Inert Metal explosives, Tungsten sulfite is used in high temperature lubricants, Tungsten compounds are used to create ceramic glazes and in the tanning industry, It is also used in fluorescent lighting It is used in weights and counterbalances, Because of its weight it is used in some aircraft and yachts as ballasts. It is also used in NASCAR and Formula One cars as ballasts. Highdensity alloys of tungsten with nickel, copper or iron are used in high-quality darts It is sometimes used in fishing lures to create quicker sinking flies. Some types of strings for musical instruments are wound with tungsten wires. Due to its ability to remain solid at high temperatures tungsten is also used in light globes, vacuum tube filaments, heating elements. It is also suitable for aerospace and high-temperature uses such as electrical, heating, and welding applications, notably in the gas tungsten arc welding processing. Tungsten is often used in electrodes due to its high melting point and its efficiency as an electrical conductor. Iron Complete Name of the Element: Iron How Name was Derived: From Latin word meaning Ferrum (Iron) Symbol of the Element: Fe Atomic #of the Element: 26 Atomic Mass of the Element: 55.845 Natural State of the Element: Solid Structure of the Element: 26 Protons, 30 Neutrons Characteristic Properties: it is a solid substance, has high strength, has a high melting point, is a good conductor of heat and electricity, easily corrodes (rusts) in water or damp surroundings. Occurrence: Iron is an abundant element in the universe; it is found in many stars, including the sun. Iron is the fourth most abundant element in the earth's crust, of which it constitutes about 5% by weight, and is believed to be the major component of the earth's core. Iron is found distributed in the soil in low concentrations and is found dissolved in groundwaters and the ocean to a limited extent. It is rarely found uncombined in nature except in meteorites, but iron ores and minerals are abundant and widely distributed. The principal ores of iron are hematite (ferric oxide, Fe2O3) and limonite (ferric oxide trihydrate, Fe2O3·3H2O). Other ores include siderite (ferrous carbonate, FeCO3), taconite (an iron silicate), and magnetite (ferrous-ferric oxide, Fe3O4), which often occurs as a white sand. Iron pyrite (iron disulfide, FeS2) is a crystalline gold-colored mineral known as fool's gold. Chromite is a chromium ore that contains iron. Lodestone is a form of magnetite that exhibits natural magnetic properties. Copper Complete Name of the Element: Copper How Name Was Derived: From the Latin word cyprium, after the island of Cyprus Symbol of the meaning: Cu Atomic # of the Element: 29 Atomic Mass of the Element: 63.546 Natural State of the Element: Solid Structure of the Element: 29 Protons, 35 Neutrons\ Properties: Copper, silver and gold are in group 11 of the periodic table, and they share certain attributes: they have one s-orbital electron on top of a filled d-electron shell and are characterized by high ductility and electrical conductivity. The filled d-shells in these elements do not contribute much to the interatomic interactions, which are dominated by the s-electrons through metallic bonds. Contrary to metals with incomplete d-shells, metallic bonds in copper are lacking a covalent character and are relatively weak. Occurrence: Copper is synthesized in massive stars[15] and is present in the Earth's crust at a concentration of about 50 parts per million (ppm),[16] where it occurs as native copper or in minerals such as the copper sulfides chalcopyrite and chalcocite, copper carbonates azurite and malachite and the copper(I) oxide mineral cuprite.[4] The largest mass of elemental copper discovered weighed 420 tonnes and was found in 1857 on the Keweenaw Peninsula in Michigan, US.[16] Native copper is a polycrystal, with the largest described single crystal measuring Uses: electrical conductor, jewelry, coins, plumbing