31 Ga 69.723

Gallium

post-transition metal

Properties

Atomic number
31
Atomic mass
69.723 u
Category
post-transition metal
Group
13
Period
4
Block
p-block
State (room temp)
Solid
Outer-shell electrons
3
Electronegativity
1.81 (Pauling)
Density
5.91 g/cm³
Melting point
29.76 °C
Boiling point
2399.85 °C

Electron configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p¹

Noble-gas shorthand: [Ar] 3d¹⁰ 4s² 4p¹

Electrons per shell: 2, 8, 18, 3 — that's 3 in the outermost shell.

See how electron configuration is built →

Ga
Bohr model — outer-shell electrons in blue

About Gallium

Gallium is a chemical element with symbol Ga and atomic number 31. Elemental gallium does not occur in free form in nature, but as the gallium(III) compounds that are in trace amounts in zinc ores and in bauxite. Gallium is a soft, silvery metal, and elemental gallium is a brittle solid at low temperatures, and melts at 29.76 °C (85.57 °F) (slightly above room temperature).

Position in the periodic table

Open the interactive periodic table →

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