Iron atom

Introduction 

Iron atom is a chemical element having atomic number 26 and with the symbol ‘Fe’ which in Latin means ferrum.  It is a metal in the first transition series.  Like other ‘group 8’ elements, it exists in several oxidation states. The oxidation states of iron is +2 and +3, it might also occur in higher oxidation states of about +6.  Iron (II) compounds are called ferric and iron(III) compounds are called ferrous.   Iron and its alloys are the widely used ferromagnetic materials in the modern day life.

Pure iron is softer than aluminum.  Steel can be prepared by alloying pure iron with small amounts of other metals and carbon. The alloy steel is almost 1,000 times harder than pure iron.  It is the most common element found on earth.  It reacts with air to form iron oxides also known as rust. The rusting of iron and its alloys is undesirable, and has a major economic impact. The melting point of iron is about 1535 °C. Its mechanical properties can be varied extensively by varying the carbon content in the alloy.

      Different types of Iron are

1.   Pig iron has 3.5–4.5% carbon
2.   Cast iron contains 2–4% carbon 
3.   Wrought iron has less than 0.008% carbon

Occurrence and Biological Importance of Iron atom

Occurrence of Iron atom: Iron is the fourth most abundant element in the Universe, formed from the process known as nucleosynthesis, by the fusion of silicon in huge stars. Metallic iron is rarely found on the surface of the earth because it tends to oxidize, but its oxides are diffused and represents the primary ores. About 5% of the earths curst constitutes of Iron.  Most of the Inner and outer core of earth consists of Iron-Nickel alloy which is about 35% of the total mass of the earth.  Hematite and Magnetite are the most common form of iron ore which is found in earth crust. These ores are combined with oxygen to form iron oxides. 

Biological importance of Iron atom: Iron plays a major role in biology.  Ranging from the primitive archaea to humans, all living organism has iron-proteins.  Hemoglobin is a protein containing iron.  Hemoglobin is responsible for the color of the blood.  Hemoglobin and myoglobin are the two compounds which helps in the transportation of oxygen proteins in vertebrates.  Iron is present in each and every cell of the human body. It is the basic necessity for the growth and development of a living organism.

Applications of Iron