13 Al 26.982

Aluminium

post-transition metal

Properties

Atomic number
13
Atomic mass
26.982 u
Category
post-transition metal
Group
13
Period
3
Block
p-block
State (room temp)
Solid
Outer-shell electrons
3
Electronegativity
1.61 (Pauling)
Density
2.7 g/cm³
Melting point
660.32 °C
Boiling point
2469.85 °C

Electron configuration

1s² 2s² 2p⁶ 3s² 3p¹

Noble-gas shorthand: [Ne] 3s² 3p¹

Electrons per shell: 2, 8, 3 — that's 3 in the outermost shell.

See how electron configuration is built →

Al
Bohr model — outer-shell electrons in blue

About Aluminium

Aluminium (or aluminum; see different endings) is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic, ductile metal. Aluminium is the third most abundant element (after oxygen and silicon), and the most abundant metal, in the Earth's crust.

Position in the periodic table

Open the interactive periodic table →

Data compiled from Wikipedia, PubChem, and IUPAC. Source.