Mn
Manganese is a hard, brittle transition metal essential for steel production and biology.
Physical Properties
| Atomic Mass | 54.938 u |
| Density | 7.44 g/cm³ |
| Melting Point | 1519.0 K |
| Boiling Point | 2334.0 K |
| Appearance | Silvery gray metallic |
| State at Room Temp | Solid |
Chemical Properties
| Electronegativity | 1.55 (Pauling) |
| 1st Ionization Energy | 717.3 kJ/mol |
| Electron Affinity | -50.0 kJ/mol |
| Oxidation States | +1, +2, +3, +4, +5, +6, +7 |
Atomic Properties
| Electron Configuration | [Ar] 3d5 4s2 |
| Atomic Radius | 127.0 pm |
| Covalent Radius | 139.0 pm |
| Van der Waals Radius | 197.0 pm |
Discovery
| Discovered By | Johan Gottlieb Gahn |
| Discovery Year | 1774 |
| Location | Stockholm, Sweden |
| Named After | Latin 'magnes' meaning magnet, or Italian 'manganese' |
About Manganese
Manganese is a hard, brittle, silvery-gray metal often found with iron. It is essential for all living organisms as a cofactor for many enzymes. The oxygen-evolving complex in photosystem II uses manganese to split water.
Uses & Applications
Steel production, dry cell batteries, aluminum alloys, potassium permanganate, and glass decolorizer.
Fun Fact
Manganese is essential for photosynthesis -- without it, plants could not split water to produce the oxygen we breathe.
Isotopes
| Mass Number | Abundance | Half-Life | Stable |
| 55 | 1.0% | - | Yes |
Electron Configuration
[Ar] 3d5 4s2