Element 41 · Niobium (Nb)
Niobium Bohr model: diagram and electrons per shell
The niobium Bohr model shows a niobium atom (Nb) as a small nucleus with its electrons circling it in 5 shells: 2 in shell K, 8 in shell L, 18 in shell M, 12 in shell N and 1 in shell O. This page has a rotating 3D niobium Bohr model, a flat diagram, a table of the electrons in each shell and the steps to draw it yourself.
Rotate the niobium Bohr model in 3D
Drag to orbit, scroll to zoom.
This is a Bohr model of niobium (Nb), a simplified picture of a single niobium atom. Its nucleus holds 41 protons, and a neutral niobium atom has 41 electrons, arranged around it in 5 shells (2 in shell K, 8 in shell L, 18 in shell M, 12 in shell N and 1 in shell O).
Niobium Bohr model diagram
Niobium electrons per shell
A neutral niobium atom has 41 electrons, one for each of its 41 protons. They fill the shells from the nucleus outwards: 2 in shell K, 8 in shell L, 18 in shell M, 12 in shell N and 1 in shell O.
| Shell | Shell number (n) | Electrons | Most it can hold (2n²) | Subshells |
|---|---|---|---|---|
| K | 1 | 2 | 2 | 1s2 |
| L | 2 | 8 | 8 | 2s2 2p6 |
| M | 3 | 18 | 18 | 3s2 3p6 3d10 |
| N | 4 | 12 | 32 | 4s2 4p6 4d4 |
| O | 5 | 1 | 50 | 5s1 |
How the niobium Bohr model builds up, shell by shell
Watch the niobium Bohr model come together: the nucleus first, then each shell in turn, from the innermost outwards, with its electrons joining the ring. The legend names every shell and counts its electrons, so you can read off the arrangement (2 in shell K, 8 in shell L, 18 in shell M, 12 in shell N and 1 in shell O) as it forms.
How to draw the niobium Bohr model
- Find the atomic number. Niobium has atomic number 41, so a neutral atom has 41 protons and 41 electrons.
- Draw the nucleus. Put a circle in the centre and write Nb in it. The 41 protons sit there with the neutrons.
- Draw the shells. Sketch 5 shells as rings around the nucleus. A shell holds at most 2n² electrons: 2 in the first, 8 in the second, 18 in the third and 32 in the fourth.
- Place the electrons. Fill from the inside out: 2 in shell K, 8 in shell L, 18 in shell M, 12 in shell N and 1 in shell O.
- Check the total. 2 + 8 + 18 + 12 + 1 = 41, the atomic number, so every electron is accounted for.
Atomic data for the niobium Bohr model
The numbers behind the niobium Bohr model, grouped by topic. Radii are in picometres (pm) and energies in kilojoules per mole (kJ/mol).
Identity
- Symbol
- Nb
- Atomic number
- 41
- Atomic mass
- 92.9064 u
- Family
- Transition Metals
- Position
- group 5, period 5
- Block
- d-block
Electron configuration
- Full
- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d4
- Shorthand
- [Kr] 4d4 5s1
- Electrons per shell
- 2, 8, 18, 12, 1
- Outer-shell electrons
- 1 in shell O
Ionisation energies
- I₁
- 652.1
- I₂
- 1380
- I₃
- 2416
- I₄
- 3700
- I₅
- 4877
- I₆
- 9847
- I₇
- 12100
Energy to remove each electron in turn (kJ/mol). A sharp jump means the next electron comes from an inner shell.
Atomic radii
- Calculated (pm)
- 198
- Empirical (pm)
- 145
- Covalent (pm)
- 147
Electronegativity and electron affinity
- Electronegativity (Pauling)
- 1.6
- Electron affinity (kJ/mol)
- 88.516
Oxidation states
+5
Charges the element commonly takes in compounds.
Physical properties, abundance and history of niobium
Bulk properties of niobium, how common it is, who discovered it and some of its compounds.
Physical properties
- Phase at room conditions
- Solid
- Appearance
- Gray metallic, bluish when oxidized
- Melting point
- 2476.85°C (2750 K)
- Boiling point
- 4743.85°C (5017 K)
- Density
- 8.57 g/cm³
- Thermal conductivity (W/m·K)
- 53.7
- Specific heat (J/g·K)
- 0.265
- Molar heat capacity (J/mol·K)
- 24.6
- Heat of fusion (kJ/mol)
- 26.8
- Heat of vaporisation (kJ/mol)
- 680
Abundance
- Earth's crust (mg/kg)
- 20
- Oceans (mg/L)
- 0
Discovery
- Discovered by
- Charles Hatchett
- Year
- 1801
Common compounds
- Niobium pentachloride Cl5Nb
- Niobium bromide (NbBr5) Br5Nb
- Niobium Nb
- Niobium, compd. with tin (3:1) NbSn
- Sodium niobate (NaNbO3) NaNbO3
- Niobium pentafluoride F5Nb
- Niobium boride (NbB) BNb
- Lithium niobium oxide (LiNbO3) LiNbO3
Compounds listed in the PubChem database.
Main isotopes of niobium
Isotopes of niobium share the same 41 protons but differ in neutrons. Natural isotopes come first, then the longest-lived others.
| Mass number | Natural abundance | Half-life | Decay |
|---|---|---|---|
| 91 | – | 680 y | EC, e⁺ |
| 92 | – | 34.7 My | β⁺ |
| 93 | 100 % | stable | – |
| 94 | – | 20.4 ky | β⁻ |
| 95 | – | 34.991 d | β⁻ |
| 96 | – | 23.35 h | β⁻ |
α = alpha decay, β⁻ = beta-minus, β⁺ = beta-plus, EC = electron capture, SF = spontaneous fission, p / n = proton / neutron emission.
More about niobium
- Niobium on the periodic table – properties, isotopes, uses and the full niobium page.
- Transition Metals – all transition metal elements and their trends.
- Bohr model of every element – the Bohr model of all 118 elements.