Atomic Number: 25 Period Number: 4 Group Number: 7
Manganese is a silvery-gray and brittle metal. It has free elements and minerals in nature. It is the 12th most common element found in the crust of earth. There is just one stable isotope in nature: 55Mn. The most common oxidation states of manganese are +2, +3, +4, +6 and +7. The color of them are different, such as for +2 is pink, for +7 is purple.
Railroad tracks, for example, are made with steel that contains as much as 1.2% manganese.
Nearly 90% of all of the manganese produced each year is used in the production of steel. Manganese is added to molten steel to remove oxygen and sulfur and is alloyed with steel to make it easier to form to increase steel's strength and resistance to impact. For example, railroad tracks are made with steel that contains as much as 1.2% manganese. There are many kinds of manganese, such as MnO2, MnO, KMnO4, MnSO4, MnCl2 and so on. Among them, MnO2 is the most common one, It is used in dry cell batteries to prevent the formation of hydrogen, to remove the green color in glass that is caused by the presence of iron contaminants, and as a drying agent in black paints.
Physical and Chemical properties:
Atomic Weight: 54.938045
Melting Point: 1519 K
Boiling Point: 2334 K
Density: 7.3 g/cm3
Phase at Room Temperature: Solid
Element Classification: Metal
Ionization Energy: 7.434 eV
Oxidation States: +7, +4, +3, +2
Wikipedia - Basics on Manganese
WebElements - The basic elements of Manganese
Jefferson Lab - Learning about Manganese