Aluminum Essay -- essays research papers

Aluminum, symbol Al, the most colossal surfacelic element in the earths crust. The atomic number of aluminium is 13 the element is in group 13 (IIIa) of the periodic table. Hans Christian Orstead, danish pastry chemist, first isolated aluminum in 1825, using a chemical process involving potassium amalgam. Between 1827 and 1845, Friedrich Whler, a German chemist, meliorate Oersteds process by using coatlic potassium. He was the first to account the specific gravity of aluminum and show its lightness. In 1854 Henri Sainte-Claire Deville, in France, obtained the metal by reducing aluminum chloride with sodium. Aided by the financial mountain of Napoleon III, Deville established a large-scale experimental plant and displayed nice aluminum at the Paris Exposition of 1855.Aluminum is a lightweight, silver metal. The atomic weight of aluminum is 26.9815 the element melts at 660 C (1220 F), boils at 2467 C (4473 F), and has a specific gravity of 2.7. Aluminum is a potently electr opositive metal and extremely reactive. In contact with air, aluminum quick becomes c everywhereed with a tough, transparent layer of aluminum oxide that resists further acrid action. For this reason, materials made of aluminum do not tarnish or rust. The metal reduces many other metallic compounds to their base metals. For example, when thermite (a mixture of powdered press oxide and aluminum) is heated, the aluminum rapidly removes the oxygen from the iron the heat of the reaction is equal to melt the iron. This phenomenon is used in the thermite process for welding iron .The oxide of aluminum is amphotericshowing both acidic and basic properties. The most meaning(a) compounds include the oxide, hydroxide, sulfate, and mixed sulfate compounds. Anhydrous aluminum chloride is important in the oil and synthetic-chemical industries. Many gemstonesruby and sapphire, for exampleconsist mainly of transparent aluminum oxide.Aluminum is the most abundant metallic constituent in the cru st of the earth only the nonmetals oxygen and silicon are much abundant. Aluminum is never found as a free metal commonly as aluminum silicate or as a silicate of aluminum mixed with other metals much(prenominal) as sodium, potassium, iron, calcium, and magnesium. These silicates are not efficacious ores, for it is chemically difficult, and therefore an expensive process, to extract aluminum from them. bauxite an impure h... ...cling of such containers is an increasingly important energy-conservation measure. Aluminums resistance to corrosion in salt body of water also makes it useful in boat hulls and various aquatic devices.A wide variety of coating alloys and wrought alloys can be fain that give the metal greater strength, castability, or resistance to corrosion or high temperatures. Some new alloys can be used as armor plate for tanks, personnel carriers, and other military vehicles.In 1886 the creative activity production of aluminum was less than 45 kg (less than 100 lb ), and its monetary value was more than $11 per kg (more than $5 per lb). In 1989, by contrast, the estimated founding production of primary aluminum was 18 million metric hemorrhoid and an estimated 4 million metric tons was produced in the joined States alone, whereas the wrong of aluminum was less than $2 per kg. U.S. consumption, by major markets, consisted of containers and packaging, 31 per centum building and construction, 20 percent transportation, 24 percent electric equipment, 10 percent consumer durables, 9 percent and miscellaneous, 6 percent. In 1989, recycled aluminum accounted for over 20 percent of total aluminum consumption in the United States.