|
41
Nb
92.9064
Niobium |
Appearance & Characteristics | Reactions |
Other Forms Radius | Conductivity | Abundance
General:
| Name: Niobium | Symbol: Nb |
| Group: Trans. Met. | Atomic weight: 92.9064 |
| Density @ 293 K: 8.57 g/cm3 | Atomic volume: 10.87 cm3/mol |
| Group: Trans. Met. | Discovered: 1801 |
States
| State (s, l, g): solid | |
| Melting point: 2741.2 K | Boiling point: 5031 K |
| Heat of fusion: 26.40 kJ/mol | Heat of vaporization: 682.0 kJ/mol |
Energies
| 1st ionization energy: 663.8 kJ/mole | |
| Electronegativity: 1.6 | 2nd ionization energy: 1381.7 kJ/mole |
| Electron affinity: 86.2 kJ/mole | 3rd ionization energy: 2416 kJ/mole |
| Specific heat: 0.26 J/gK | Heat atomization: 726 kJ/mole atoms |
Oxidation & Electrons
| Shells: 2,8,18,12,1 | Electron configuration: [Kr] 4d4 5s1 |
| Minimum oxidation number: -1 | Maximum oxidation number: 5 |
| Min. common oxidation no.: 0 | Max. common oxidation no.: 5 |
Appearance & Characteristics
| Structure: bcc: body-centered cubic | Color: silvery-white |
| Uses: stainless steels, magnets | Toxicity: |
| Hardness: mohs | Characteristics: soft |
Reactions
| Reaction with air: none, w/ht => Nb2O3 | |
| Reaction with 6 M HCl: none | Reaction with 6 M HCl: none |
| Reaction with 15 M HNO3: | Reaction with 6 M NaOH: none |
Other Forms
| Number of isotopes: 1 | Hydride(s): NbH NbH2 |
| Oxide(s): NbO NbO2 Nb2O5 | Chloride(s): NbCl3 NbCl4 NbCl5 |
Radius
| Ionic radius (2- ion): pm | Ionic radius (1- ion): pm |
| Atomic radius: 146 pm | Ionic radius (1+ ion): pm |
| Ionic radius (2+ ion): pm | Ionic radius (3+ ion): 86 pm |
Conductivity
| Thermal conductivity: 53.7 J/m-sec-deg | |
| Electrical conductivity: 80 1/mohm-cm | Polarizability: 15.7 A^3 |
Abundance
| Source: columbite (oxide) | |
| Rel. abund. solar system: -0.156 log | Abundance earth's crust: 1.3 log |
| cost, pure: 18 $/100g | cost, bulk: $/100g |
