11
Na
Alkali metal

Sodium

Atomic number 11 · Period 3 · Block S

Na · Sodium
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Understanding the element

Sodium (Na) is chemical element 11. It belongs to the alkali 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 common salts, chemical synthesis and reactor coolant.

common saltschemical synthesisreactor coolant
Standard atomic weight22.98976928(2)

What its position in the table tells us

Sodium sits in period 3, group 1 and the S block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.

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

Scientific sources

Element identity
Atomic number11
Group1
Period3
BlockS
CategoryAlkali metal
PhaseSolid