## Niobium |

Symbol | Nb |
---|---|

Latin name | Niobium |

Atomic number | 41 |

Period | 5 |

Element category | Transition elements |

Relative atomic mass | 92.90638 |

Group | V.B |

Electronegativity | 1.6 |

Oxidation numbers | 3, 5 |

Electron configuration | 1s ^{2} 2s^{2} 2p^{6} 3s^{2} 3p^{6} 3d^{10} 4s^{2} 4p^{6} 4d^{4} 5s^{1} |

Density [g/cm^{3}] | 8.57 |

State | Solid |

Melting point [°C] | 2468 |

Boiling point [°C] | 4742 |

Atomic radius [pm] | 198 |

Covalent radius [pm] | 137 |

Thermal conductivity [W m^{-1}K^{-1}] | 53.7 |

Heat capacity [J K^{-1}g^{-1}] | 0.265 |

Discovery | 1801 |

Hardness [Mohs scale] | 6.0 |

Vickers hardness [MPa] | 1320 |

Brinell hardness [MPa] | 736 |

Young's modulus [GPa] | 105 |

Electrical conductivity [S m^{-1}] | 6.7 · 10 ^{6} |

Shear modulus [GPa] | 38 |

1.st ionization energy [eV] | 6.7589 |

2.nd ionization energy [eV] | 14.32 |

3.rd ionization energy [eV] | 25.04 |

Stable isotopes | 1 |

Unstable isotopes | 21 |