Atomic number 42
Molybdenum
Transition metal
Quick facts
- Atomic mass
- 95.950
- Group
- 6
- Period
- 5
- State (STP)
- solid
- Electronegativity
- 2.16
- Common ox. states
- +4, +6
Properties
Electron configuration
[Kr] 4d⁵ 5s¹
- Ionization energy
- 684.3 kJ/mol
- Electron affinity
- 71.9 kJ/mol
- Melting point
- 2896.00 K (2622.8 °C)
- Boiling point
- 4912.00 K (4638.9 °C)
How it bonds
Molybdenum shows oxidation states +2 through +6, with +6 (MoO₃) the most common. Like chromium, the half-filled 4d⁵ 5s¹ configuration is the stable one. Essential cofactor in nitrogenase, the enzyme that fixes atmospheric N₂ in legumes.