Iron is a transition metal belonging to the eighth column of the periodic table. It has an atomic number of 26. It constitutes the major part of the inner and outer core and is the most abundant element in earth’s crust by mass. An iron-nickel alloy is believed to be 35 percent of the total mass of earth. Iron’s symbol is Fe, derived from the Latin word for iron, Ferrum.
It is the sixth most abundant element in the universe and even the red color of Mars surface is believed to be because of iron-oxide rich regolith. Iron plays a very important role in our lives. Other group eight elements are osmium, hassium and ruthenium.
Iron exists in a wide range of oxidation states (-2 to +6) just like all other group eight members. However, the most commonly found are +2 and +3 states. When in its pure form, iron is grayish soft and very reactive. Iron gains its signature hardness and strength after alloying with other metals, like carbon. It easily corrodes and rusts upon reacting with air and moisture. Iron is malleable and is a fairly good conductor of heat and electricity. Iron, cobalt and nickel are the naturally magnetic elements and iron is the most magnetic of all. Ferrite is the most abundantly found form of iron and is called Alpha Iron. Iron is found in four allotropes. Meteorites are also largely made up of iron.
The largest use of iron is manufacture of steel, an iron-carbon alloy. Man is known to be producing steel for over 4000 years now and only copper and its alloys have been produced for a longer period than iron. Other commonly used iron alloys are pig iron, cast iron and wrought iron.
Steel is used for construction of buildings, structures, vehicles, ships, tools and so much more. Stainless Steel is used for manufacturing surgical instruments, household appliances and industrial equipment among others. Iron is a very important nutrient for both plants and animals. As a part of hemoglobin, it plays an important part in the transportation of oxygen in the body. Plants need iron in chloroform for the all important photosynthesis procedure.
Listed below are some very interesting and rarely known facts about iron:
- The word iron is derived from Anglo-Saxon word ‘iron’ which means metal.
- Iron makes up 5.6% of earth’s crust, making it one of the most abundant metals.
- Too much of iron in body can be dangerous. While 20mg of iron per kilogram of body weight is considered toxic, 60mg can be fatal.
- Iron is a structural constituent of sun, stars and planets like Mars.
- Iron Age succeeded Bronze Age and started around 1200BC.
- Cast iron is created by heating iron alloy into liquid state and then pouring it in a mould. This procedure was devised by Chinese in 5th Century BC.
- Human body acquires necessary iron nutrition through diet. Red meat, green leafy vegetables, fish and beans are a good source of dietary iron.
- The process of smelting actually hardens the iron and makes it strong enough to be used for various purposes.
- Iron’s alloy, steel can be interestingly, 1000 times harder than iron itself.
- Presence of iron in blood gives it the deep red color.
- The iron tools were first manufactured in around 3600 BC.
- Iron is the most widely used metal and accounts for 95% of total metal production of the world.
- Powdered iron is also used for manufacturing automobile parts and magnetic alloys.
- Saturn and Jupiter are two planets with very iron-rich cores.
- China is world’s largest iron producing country and accounts for 33% of world’s iron production.
- Iron has a melting point of 1538°C and a boiling point of 2862°C.
- Most of the iron found on the surface of the planet earth is in shape of iron oxides because iron oxidizes upon contact with air. The most common iron oxides are hematite and magnetite.