Periodic TableAll elementsGallium
No. 031
Ga
69.723 u
Element · Post-Transition Metal

Gallium

Gallium (镓, symbol Ga) is chemical element number 31, a Post-Transition Metal in period 4, group 13 of the periodic table, with a standard atomic weight of about 69.723. Soft metal that melts in your hand. Used in semiconductors and LEDs.

Period 4Group 13[Ar] 3d¹⁰ 4s² 4p¹

Properties

Atomic number31
SymbolGa
Atomic mass69.723 u
CategoryPost-Transition Metal
Period4
Group13
Electron configuration[Ar] 3d¹⁰ 4s² 4p¹
Electronegativity1.81
Covalent radius122 pm
Density5.907 g/cm³
Melting point302.91 K
Boiling point2477 K
DiscoveryLecoq de Boisbaudran, 1875

Overview

Soft metal that melts in your hand. Used in semiconductors and LEDs. Gallium (Ga) holds position 31 in the periodic table, a Post-Transition Metal in period 4, group 13. As a post-transition metal it is fairly soft with a low melting point, turning up in alloys, solders and coatings.

With 3 electrons in its outermost shell, Gallium bonds accordingly; full configuration [Ar] 3d¹⁰ 4s² 4p¹, electronegativity 1.81. At room temperature it is normally a solid (a very low melting point); it melts near 302.91 K (29.8 °C), boils near 2477 K (2203.9 °C), has a density around 5.907 g/cm³.

Common applications range across Electronics / Semiconductors and Research. It was first described by Lecoq de Boisbaudran in 1875.

Electron shells

Ga31

Electrons per shell: 2 · 8 · 18 · 3

Main uses

Hazard

LowNo special hazard flags.

Compounds containing Gallium

No compounds in this knowledge base contain Gallium yet.

Data sources

Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.