Iron - A Metal And Dietary Element

Iron is relatively abundant in the earth's crust. It is even found in the sun and many stars in substantial amount and its nucleus is very stable.

Metal Iron

It is silvery, shiny metal with magnetic properties. As a pure metal it does not see much commercial use, but its alloys with carbon and other metals have great demand in many projects worldwide. It is chemically reactive metal which leads to its extensive corrosion in moist air or high temperatures for long periods of time.

Hematite is the most commonly found iron ore from which iron metal is extracted by reduction reaction with carbon. Many minerals contain iron as well like taconite and magnetite, usually seen on the beaches ad black sand.

Physical and chemical properties

Melting point of iron stands at 1535 degree Celsius and boiling point is 2750 degree Celsius. The specific gravity comes out to be 7.874 (20 degree Celsius). It has a valence of 2, 3, 4, and 6. The allotropic forms are known ferrites: ferrite a, b, g and d. The 'a' form has magnetic properties, but when it is changed to the 'b' form iron loses its magnetic properties, although the lattice structure remains the same. Iron has 14 known isotopes; the common iron contains a mixture of just 4 isotopes.

Uses

Wrought iron is an alloy of iron which has extremely little content of carbon, and fibrous additions which are called as slag. This slag gives wrought iron a 'grain' that resembles to wood. This is visible when it is etched or bent to extreme positions. Wrought iron alloy becomes hard, flexible and ductile and can be conveniently welded to produce a variety of items like nails, rivets, water and steam pipes, railways coupling, nuts and bolts, straps for timber roof and ornamental works. Steel alloy, however, has more carbon content and is extensively used in places where the corrosion of iron has deep negative impact on mechanical performance and therefore, environment resistant stainless steel is used. Carbon steel alloy is formed with small quantity of S, Si, Mn and P.

Dietary iron

Iron is important for human life as well as plant and animal life. All cells in the human system contain iron. Tissues and cells are oxidized because of iron as the iron-rich red blood cells travel through the body containing oxygenated blood and picking up carbon dioxide so that it can be excreted. The functioning of immune system is improved because of iron as it produces energy and increases the supply of oxygen throughout the system.

The intake of iron is necessary as it occurs as a mineral, forming an important part of hemoglobin. Muscle mechanism is supported by oxygen carried by iron. Also, iron aids the body in resisting to stress and ailments. Iron intake depends on age, gender and the amount already present in a person's body. The body inevitable absorbs more or less of iron from food according to requirements. Iron-rich foods include heme iron- well absorbed iron- foods like meat products. The other is non-heme iron foods like eggs, dairy products, pasta, leafy vegetables and dried fruits.