Carl Wilhelm Scheele proposed the existence of the element manganese in early 1774. However, Swedish chemist Johan Gottlieb Gahn was the first to obtain manganese metal and observe it in late 1774 by heating the mineral pyrolusite (MnO2) in the presence of charcoal. The name originates from the Latin word "mangnes" meaning magnet because pyrolusite (Mn02), corrupt form of magnesia, has magnetic properties.
Name: Manganese
Symbol: Mn
Atomic number: 25
Atomic weight: 54.938
State: solid
Group, period, block: 7, 4, d
Color: silvery metallic
Classification: transition metal
Electron configuration: 4s2 3d5
2,8,13,2
Physical properties
Density: 7.21 g/cm-3
Melting point: 1519 K, 1246 °C, 2275 °F
Boiling point: 2334 K, 2061 °C, 3742 °F
Atomic properties
Oxidation states: 7, 6, 5, 4, 3, 2, 1, -1, -2, -3
Electronegativity: 1.55 (Pauling scale)
Ionization energies: 1st: 717.3 kJ·mol-1
Covalent radius: 139±5 (low spin), 161±8 (high spin) pm
Van der Waals radius: no data
- Mn
Electron Configuration
Isotopes
There is only one naturally occurring isotope of manganese exists, 22Mn.