Al
Aluminium
Element 13 · Post-transition metal
Aluminium (Al)
Aluminium is the most abundant metal in Earth’s crust. Light, non-magnetic and corrosion-resistant, it is the second most used metal after iron.
- Post-transition metal
- Period 3
- Group 13
- p-block
- solid at room temperature
Key properties
- Atomic mass
- 26.9815
- u
- Electron configuration
- [Ne] 3s2 3p1
- Melting point
- 660.3 °C
- 933.44 K
- Boiling point
- 2,518.9 °C
- 2,792 K
- Density
- 2.7 g/cm³
- Electronegativity
- 1.61
- Pauling
- Atomic radius
- 184 pm
- van der Waals
- 1st ionisation energy
- 5.986 eV
Compare with every element:Electronegativity chartAtomic radius chartIonisation energy chartDensity chart of the elementsMelting point chartElectron configuration chart
Did you know?
Notable facts about aluminium
- 01
Before the Hall–Héroult process (1886), aluminium was more precious than gold.
- 02
A cap of aluminium sat on top of the Washington Monument in 1884 as a showpiece of the rare metal.
- 03
Recycling aluminium uses about 5% of the energy needed to make it from ore.
Applications
What is aluminium used for?
- Drink cans and foil
- Aircraft and vehicle bodies
- Power transmission lines
- Window frames and construction
History
Discovery & name origin
Atomic structure
Atomic properties
Atomic structure
Atomic properties
- Atomic number
- 13
- Atomic mass
- 26.9815 u
- Group
- 13
- Period
- 3
- Block
- p-block
- Electron configuration
- [Ne] 3s2 3p1
- Full configuration
- 1s2 2s2 2p6 3s2 3p1
- Electrons per shell
- 2, 8, 3
- Electronegativity (Pauling)
- 1.61
- Electron affinity
- 0.441 eV
- Atomic radius (van der Waals)
- 184 pm
- Stable isotopes
- 1
Oxidation states
Highlighted: common oxidation states (+3).
Successive ionisation energies
Energy to remove each electron in turn (kJ/mol). Big jumps show where a new, inner shell begins.
- 1st577.5
- 2nd1,816.7
- 3rd2,744.8
- 4th11,577
- 5th14,842
- 6th18,379
- 7th23,326
- 8th27,465
Physical
Physical properties & colour
Physical
Physical properties & colour
- State at 20 °C
- Solid
- Melting point
- 933.44 K · 660.3 °C · 1,220.5 °F
- Boiling point
- 2,792 K · 2,518.9 °C · 4,565.9 °F
- Density
- 2.7 g/cm³
- Molar heat capacity
- 24.2 J/(mol·K)
- Appearance
- Silvery grey metallic
- CPK model colour
- Copied
The CPK colour is the convention used for this element’s atoms in molecular models.
FAQ
Aluminium questions
What is Al on the periodic table?
Al is the symbol for aluminium, element 13 on the periodic table. It sits in group 13, period 3, in the post-transition metal category, and has an atomic mass of 26.9815.
What is the atomic number of aluminium?
Aluminium has atomic number 13, so every aluminium atom has 13 protons in its nucleus. Its symbol is Al and its atomic mass is 26.9815.
Who discovered aluminium?
Aluminium was discovered by Hans Christian Ørsted in 1825 (Denmark). The name comes from Latin alumen, “alum”.
What is aluminium used for?
Aluminium is used for: drink cans and foil; aircraft and vehicle bodies; power transmission lines; window frames and construction.
Is aluminium a metal?
Yes. Aluminium is a post-transition metal, one of the metallic elements.
What is the electron configuration of aluminium?
The electron configuration of aluminium is [Ne] 3s2 3p1. Its 13 electrons are arranged in shells as 2, 8, 3.