12
Mg
Alkaline earth metal

Magnesium

Atomic number 12 · Period 3 · Block S

Mg · Magnesium
Mendeleev.com

Understanding the element

Magnesium (Mg) is chemical element 12. It belongs to the alkaline-earth metals, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.

Where do we encounter it?

In practice, it turns up most often in alloys, fireworks and biology.

alloysfireworksbiology
Standard atomic weight[24.304, 24.307]

What its position in the table tells us

Magnesium sits in period 3, group 2 and the S block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.

Worth remembering
Magnesium has a characteristic place in the periodic table that helps explain both its chemistry and its practical uses

Scientific sources

Element identity
Atomic number12
Group2
Period3
BlockS
CategoryAlkaline earth metal
PhaseSolid