13 Al Aluminium 26.982
Post-transition metal
Aluminium 铝
[Ne] 3s² 3p¹
- Period 3
- Group 13
- Block p
- Solid
Electron configuration
1s² 2s² 2p⁶ 3s² 3p¹
Orbital diagram (valence)
3s ↑↓
3p ↑
- Electrons per shell
- 2, 8, 3
- Unpaired electrons
- 1
- Zeff (Slater)
- 3.50
Properties
- Atomic weight
- 26.982
- Electronegativity (Pauling)
- 1.61
- First ionization energy
- 577.6 kJ/mol
- Electron affinity
- 42.55 kJ/mol
- Covalent radius
- 121 pm
- van der Waals radius
- 184 pm
- Melting point
- 933.4 K
- Boiling point
- 2792 K
- Density
- 2.7 g/cm³
- Melting / boiling point
- 660.3 °C / 2518.8 °C
- Common oxidation states
- +3
- Discovered
- Known since antiquity
Natural isotopes
| Mass number A | Abundance |
|---|---|
| 27Al | 100.00 % |
Isotope masses: AME2020; abundances: IUPAC/CIAAW representative values.
Successive ionization energies
The big jumps appear where core electrons start to be removed. Ionization energies from the NIST Atomic Spectra Database.
Aluminium in the course
The lessons that discuss this element most (ranked by mentions).
- Extracting metals Transition metals
- Boron, aluminium, carbon, silicon and the inert pair The main-group elements
- Ellingham diagrams and metal extraction Entropy and free energy
- Electrolysis: driving reactions with electricity Redox and electrochemistry
- Complex ions and formation constants Precipitation and complex ions
- Mole ratios and mass calculations Reactions and stoichiometry
- Oxygen and sulfur The main-group elements
- Naming ions and compounds Reactions and stoichiometry
Lab experiments with Aluminium
Crystal structures
- Face-centred cubic (ccp) lattice parameter a = 404.9 pm
Periodic trend
Group 13
Data: PubChem periodic table (public domain); atomic weights are IUPAC abridged standard values; covalent radii from Cordero et al. (2008).