Manganese

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Attribution: Tomihahndorf

Animated Manganese

History

From the Latin word magnes, magnet, from magnetic properties of pyrolusite. Recognized by Carl Wilhelm Scheele, Torbern Olof Bergman, and others as an element and isolated by Gahn in 1774 by reduction of the dioxide with carbon.

Sources

Manganese minerals are widely distributed, with oxides, silicates, and carbonates being the most common. Large quantities of manganese nodules are found on the ocean floor and may become a source of manganese. These nodules contain about 24% manganese, together with many other elements in lesser abundance.

Most manganese today is obtained from ores found in Russia, Brazil, Australia, South Africa, Gabon, and India. Pyrolusite and rhodochrosite are among the most common manganese minerals. The metal is obtained by reduction of the oxide with sodium, magnesium, aluminum, or by electrolysis.

Uses

The dioxide (pyrolusite) is used as a depolarizer in dry cells and is used to "decolorize" glass that is colored green by impurities of iron. Manganese by itself colors glass an amethyst color and is responsible for the color of true amethyst. The dioxide is also used in the preparation of oxygen and chlorine and in drying black paints. The permanganate is a powerful oxidizing agent and is used in quantitative analysis and in medicine.

Manganese is widely distributed throughout the animal kingdom. It is an important trace element and may be essential for utilization of vitamin B1.

General Info

AtomicNumber
25
Symbol
Mn
Name
Manganese

Atomic Info

Appearance
AtomicWeight
54.938045(5)
Color
9C7AC7
ElectronicConfiguration
[Ar] 3d5 4s2
ElectronegativityInPauling
1.55
AtomicRadiusInPM
139
IonRadiusInPM
67 (+2)
VanDerWaalsRadiusInPM
IEinKJmol
717
EAinKJmol
0
OxidationStates
-3, -2, -1, 1, 2, 3, 4, 5, 6, 7
StandardState
solid
BondingType
metallic
MeltingPoint
1519
BoilingPoint
2334
Density
7.47
State
Transition metal
DiscoveredYear
1774