12 Mg 24.305

Magnesium

alkaline earth metal

Properties

Atomic number
12
Atomic mass
24.305 u
Category
alkaline earth metal
Group
2
Period
3
Block
s-block
State (room temp)
Solid
Outer-shell electrons
2
Electronegativity
1.31 (Pauling)
Density
1.738 g/cm³
Melting point
649.85 °C
Boiling point
1089.85 °C

Electron configuration

1s² 2s² 2p⁶ 3s²

Noble-gas shorthand: [Ne] 3s²

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

See how electron configuration is built →

Mg
Bohr model — outer-shell electrons in blue

About Magnesium

Magnesium is a chemical element with symbol Mg and atomic number 12. It is a shiny gray solid which bears a close physical resemblance to the other five elements in the second column (Group 2, or alkaline earth metals) of the periodic table:they each have the same electron configuration in their outer electron shell producing a similar crystal structure. Magnesium is the ninth most abundant element in the universe.

Position in the periodic table

Open the interactive periodic table →

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