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Extraction of iron ore Iron is a chemical element with the symbol Fe (L.: Ferrum) and atomic number 26. Iron is a group 8 and period 4 metal. Iron is notable for being the final element produced by stellar nucleosynthesis, and thus the heaviest element which does not require a supernova or similarly cataclysmic event for its formation. It is therefore the most abundant heavy metal in the universe. Notable characteristics Iron is the most abundant metal on Earth, and is believed to be the tenth most abundant element in the universe. Iron is also the second most abundant element by mass, making up 34% of the mass of the Earth; the concentration of iron in the various layers of the Earth ranges from high at the inner core to about 5% in the outer crust. It is possible the Earth's inner core consists of a single iron crystal, although it is more likely to be a mixture of iron and nickel. The large amount of iron in the Earth is thought to create its magnetic field. Iron is a metal extracted from iron ore, and is almost never found in the free elemental state. In order to obtain elemental iron, the impurities must be removed by chemical reduction. Iron is used in the production of steel, an alloy or solid solution of different metals, and some non-metals, particularly carbon. Nuclei of iron have some of the highest binding energies per nucleon, surpassed only by the nickel isotope 62Ni. The universally most abundant of the highly stable nucleides is, however, 56Fe. This is formed by nuclear fusion in the stars. Although a further tiny energy gain could be extracted by synthesizing 62Ni, conditions in stars are not right for this process to be favoured. [citation needed] When a very large star contracts at the end of its life, internal pressure and temperature rise, allowing the star to produce progressively heavier elements, despite these being less stable than the elements around mass number 60, known as the "iron group". This leads to a supernova. Some cosmological models with an open universe predict that there will be a phase where as a result of slow fusion and fission reactions, everything will become iron. ↑ Fe ↓ Ru Applications Iron is the most used of all the metals, comprising 95 percent of all the metal tonnage produced worldwide. Its combination of low cost and high strength mak indispensable, especially in applications like automobiles, the hulls of large ship structural components for buildings. Steel is the best known alloy of iron, and s of the forms that iron can take include: Pig iron has 4% – 5% carbon and contains varying amounts of contamin such as sulfur, silicon and phosphorus. Its only significance is that of an intermediate step on the way from iron ore to cast iron and steel. Cast iron contains 2% – 4.0% carbon , 1% – 6% silicon , and small amo of manganese. Contaminants present in pig iron that negatively affect th material properties, such as sulfur and phosphorus, have been reduced t acceptable level. It has a melting point in the range of 1420–1470 K, wh lower than either of its two main components, and makes it the first prod to be melted when carbon and iron are heated together. Its mechanical properties vary greatly, dependent upon the form carbon takes in the all 'White' cast irons contain their carbon in the form of cementite, or iron carbide. This hard, brittle compound dominates the mechanical propertie white cast irons, rendering them hard, but unresistant to shock. The bro surface of a white cast iron is full of fine facets of the broken carbide, a v pale, silvery, shiny material, hence the appellation. In grey iron, the carb exists free as fine flakes of graphite , and also, renders the material britt due to the stress-raising nature of the sharp edged flakes of graphite. A variant of grey iron, referred to as ductile iron is specially treated with tr amounts of magnesium to alter the shape of graphite to sheroids, or nod vastly increasing the toughness and strength of the material. period Extraction of Iron. Iron is extracted from its ore in the blast furnace. The main iron ore is called hematite. Hematite is iron(III) oxide - Fe2O3. The iron ore contains impurities, mainly silica (silicon dioxide). Limestone (calcium carbonate) is added to the iron ore which reacts with the silica to form molten calcium silicate in the blast furnace. The calcium silicate (called slag) floats on the liquid iron. Since iron is below carbon in the reactivity series, iron in the ore is reduced to iron metal by heating with carbon (coke). It is actually carbon monoxide which does the reducing in the blast furnace Source of information. From Internet