|Appearance||lustrous metallic with a grayish tinge|
|Standard atomic weight A(Fe)||55.845(2)|
|Atomic number (Z)||26|
|Element category||transition metal|
|Electron configuration||[Ar] 3d6 4s2|
|Electrons per shell||2, 8, 14, 2|
The production of iron or steel is a process done in two main stages. In the first stage pig iron is created in a blast furnace. On the other hand, it may be directly reduced. In the second stage, pig iron is transformed to wrought iron, steel, or cast iron.
Industrial iron making starts with iron ores, principally hematite, which has a nominal formula Fe2O3, and magnetite, with the formula Fe3O4. These ores are reduced to the metal by treatment with carbon which is called as carbothermic reaction. The adaptation is typically conducted in a blast furnace at temperatures of about 2000 °C. Carbon is provided in the form of coke. The process also contains a flux such as limestone, which is used to eliminatesiliceous minerals in the ore, which would otherwise clog the furnace. The coke and limestone are fed into the top of the furnace, while a massive blast of air heated to 900 °C, about 4 tons per ton of iron, is forced into the furnace at the bottom.
Some iron at high temperature bottom part of the furnace reacts directly with the coke:
The flux that tries to melt impurities in the ore is principally limestone (calcium carbonate) and dolomite (calcium-magnesium carbonate). Other fluxes are used on the details of the ore. At thehigh temperature of the furnace the limestone flux decomposes to calcium oxide (also known as quicklime):
Then calcium oxide mixes with silicon dioxide to create a liquid slag.
The slag dissolve sat the high temperature of the furnace. In the base of the furnace, the molten slagfloats on top of the denser molten iron and apertures in the corner of the furnace are opened to run off the iron and the slag individually. The iron, once cooled, is called pig iron, while the slag material can be used in road construction or to improve mineral-poor soils for agriculture.
Due to environmental concerns, other methods of producing iron have been developed.
Natural gas is to some extent oxidized (with heat and a catalyst):
Iron ore is next treated with the gases in a furnace, creating solid sponge iron:
|Phase at STP||solid|
|Melting point||1811 K (1538 °C, 2800 °F)|
|Boiling point||3134 K (2862 °C, 5182 °F)|
|Density (near r.t.)||7.874 g/cm3|
|when liquid (at m.p.)||6.98 g/cm3|
|Heat of fusion||13.81 kJ/mol|
|Heat of vaporization||340 kJ/mol|
|Molar heat capacity||25.10 J/(mol·K)|
The properties of iron and its alloys can be simplified using a variety of tests, including the Brinell test, Rockwell test and the Vickers hardness test. The data on iron is so reliable that it is often used to calibrate to compare tests. Nevertheless, the mechanical properties of iron are drastically affected by the different results of purity: pure, individual crystals of iron are less hard than aluminum,and the purest industrially produced iron (99.99%) has a toughness of 20–30 Brinell. An increasing in the amount of carbon content will cause a significant increase in the toughness and tensile strength of iron. Highest hardness of 65 Rc is achieved with a 0.6% carbon content, although the alloy has low tensile strength. Due to the softness of iron, it is much simpler to work with than its heavier congeners ruthenium and osmium. According to which its significance for environmental cores, the physical properties of iron at high pressures and temperatures have also been studied widely. The form of iron that is steady under normal conditions can be subjected to pressures up to 15 GPa before ittransform into a high-pressure form, as described in the next section.
Iron shows different attributeof chemical properties of the transition metals, namely the tendency to form variable oxidation states differentiated by steps of one and a very large coordination and organometallic chemistry: certainly, it was the discovery of an iron compound, ferrocene, that revolutionized the latter field in the 1950s. Sometimes iron considered as a prototype for the entire building block of transition metals, due to its loads and the immense role it has played in the technological progress of humanity. In its configuration 26 elements are arranged [Ar]3d64s2, of which the 3d and 4s electrons are close in energy.
Iron is used in various sectors such as electronics, manufacturing, automotive, and construction and building.