Manganese is a chemical element that has the symbol Mn and atomic number 25. It is found as the free element in nature (often in combination with iron), and in many minerals. The free element is a metal with important industrial metal alloy uses. Manganese ions are variously colored, and are used industrially as pigments and as oxidation chemicals. Manganese (II) ions function as cofactors for a number of enzymes; the element is thus a required trace mineral for all known living organisms.
Manganese is a gray-white metal resembling iron. It is a hard metal and is very brittle, fusible with difficulty, but easily oxidized. Manganese metal and its common ions are paramagnetic. This means that, while manganese metal does not form a permanent magnet, it does exhibit strong magnetic properties in the presence of an external magnetic field.
Technical Data
Symbol |
Mn |
Ionic radius(6-coordinate)/pm III |
58(ls) 64.5(hs) |
Atomic number |
25 |
Ionic radius(6-coordinate)/pm II |
67 |
No. of naturally occurring isotopes |
1 |
Density (25°C)/gcm-3 |
7.43 |
Atomic weight |
54.938 |
Melting point / °C |
1244 |
Electronic configuration |
[Ar]3d54s2 |
Boiling point / °C |
2060 |
Metal radius(12-coordinate)/pm |
127 |
ΔHfus/kJmol-1 |
-13.4 |
Ionic radius(6-coordinate)/pm VII |
46 |
ΔHvap/kJmol-1 |
221 (+/-8) |
Ionic radius(4-coordinate)/pm VI |
25.5 |
ΔHf(monoatomic gas)/kJmol-1 |
281 (+/-6) |
Ionic radius(4-coordinate)/pm V |
33 |
Electrical resistivity |
185 |
Ionic radius(6-coordinate)/pm IV |
53 |
Electronegativity χ |
1.5 |
Evaporation Techniques
Temperature (oC) @Vap. Pressure |
Techniques |
Remarks |
10-8 Torr |
10-6 Torr |
10-4 Torr |
Electron Beam |
Crucible |
Coil |
Boat |
507 Sublimes |
572 Sublimes |
647 Sublimes |
Good |
Al2O3 |
Tungsten |
Tungsten, Molybdenum & Tantalum |
|