3D Bohr-model representation of the Aluminium atom (symbol Al, atomic number Z=13). Electron shell configuration: 2, 8, 3 electrons.
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Bohr model · educational
Bohr model of aluminium
Aluminium (Al) has 13 electrons, spread over 3 shells. The diagram places them on circles around the nucleus, from the K shell — the closest — outward.
| Shell | Electrons |
|---|---|
| K (n = 1) | 2 |
| L (n = 2) | 8 |
| M (n = 3) | 3 |
The Bohr model is a teaching picture: electrons do not travel in circular orbits, but the number of electrons per shell is exact.
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Metallic bonding
Delocalized electron gas model. Consequences: conductivity, ductility, metallic luster.
9 minElectron configuration
Full1s² 2s² 2p⁶ 3s² 3p¹
Short[Ne] 3s² 3p¹
Valence electrons3
KLMNOPQ shells
K2
L8
M3
Electronegativity
Pauling1.61
Allen1.613
Mulliken (eV)—
Atomic radii
Empirical125 pm
Calculated118 pm
Covalent121 pm
Van der Waals184 pm
Ionic radii (Shannon-Prewitt)
+353 pm
Successive ionisation energies
I₁577.5 kJ/mol
I₂1816.7 kJ/mol
I₃2744.8 kJ/mol
I₄11577 kJ/mol
I₅14842 kJ/mol
Electron affinity41.8 kJ/mol
Oxidation states
-2-1+1+2+3
Bold states = most common.
Warm-up
Aluminium — do you remember?
3 questions on this page. The right answer shows every time, and nothing is asked of you to play.
No account · one minute