Niobium (Nb)
Niobium (Nb) is element 41 of the periodic table, a transition metal in period 5 and group 5. Its standard atomic weight is 92.90637, so one mole of niobium atoms has a mass of 92.90637 g. At room temperature it is a solid; it melts at 2476.85 °C and boils at 4743.85 °C.
| Atomic number | 41 |
|---|---|
| Symbol | Nb |
| Standard atomic weight | 92.90637 |
| Molar mass | 92.90637 g/mol |
| Category | Transition metal |
| Group | 5 |
| Period | 5 |
| Block | d-block |
| Electron configuration | [Kr] 5s1 4d4 |
| Oxidation states | +5, +3 |
| Electronegativity (Pauling) | 1.6 |
| Atomic radius (van der Waals) | 207 pm |
| First ionisation energy | 6.759 eV (652.1 kJ/mol) |
| Electron affinity | 0.893 eV |
| State at room temperature | Solid |
| Melting point | 2750 K (2476.85 °C) |
| Boiling point | 5017 K (4743.85 °C) |
| Density | 8.57 g/cm³ |
| Discovered | 1801 |
Group 5
Calculate with Niobium
Atomic weight: IUPAC CIAAW standard atomic weight. Other properties: PubChem (U.S. National Library of Medicine, public domain). Values such as melting point and radius depend on how they were measured; check a data book for precise work.