41Nb92.90637
Niobium
Transition Metal
Solid at STP
Period 5Group 5Block DDiscovered 1801
[Kr]5s1 4d4
Niobium, formerly columbium, is a chemical element with symbol Nb (formerly Cb) and atomic number 41. It is a soft, grey, ductile transition metal, which is often found in the pyrochlore mineral, the main commercial source for niobium, and columbite. The name comes from Greek mythology:Niobe, daughter of Tantalus since it is so similar to tantalum.
📖 Read more on Wikipedia →Atomic Properties
| Atomic Number | 41 |
| Atomic Mass | 92.90637 u |
| Electron Configuration | [Kr]5s1 4d4 |
| Oxidation States | +5, +3 |
| Electronegativity | 1.6 (Pauling) |
| Atomic Radius | 207 pm |
| Ionization Energy | 6.759 eV |
| Electron Affinity | 0.893 eV |
| Block | D |
Physical Properties
| Appearance | gray metallic, bluish when oxidized |
| Standard State | Solid |
| Melting Point | 2750 K (2476.8 °C) |
| Boiling Point | 5017 K (4743.9 °C) |
| Density | 8.57 g/cm³ |
| Molar Heat | 24.6 J/(mol·K) |
| CPK Color | #73C2C9 |
Classification
| Category | Transition Metal |
| Group Block | Transition metal |
| Period | 5 |
| Group | 5 |
| Block | D |
Discovery
| Year Discovered | 1801 |
| Discovered By | Charles Hatchett |
| Electron Shells | 2, 8, 18, 12, 1 |