Element 11
Sodium
Alkali metals
Sodium (Na) is in the s-block of the periodic table — group 1, period 3.
Sodium /ˈsoʊdiəm/ is a chemical element with symbol Na (from Ancient Greek Νάτριο) and atomic number 11.
Key data
- Atomic number
- 11
- Atomic mass
- 22.990 u
- Group / Period
- 1 / 3
- Block
- s-block
- Phase at STP
- Solid
- Density
- 0.968 g/cm³
- Melting point
- 97.8 °C
- Boiling point
- 882.9 °C
- Electron configuration
- [Ne] 3s1
Periodic table block
Sodium is in the s-block (group 1, period 3). Elements land in the s-block when their highest-energy electrons fill an s subshell — this includes hydrogen, helium, and the reactive metals on the far left of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Table salt (with Cl)
- •Street lamps
- •Soap
Discovery
Year: 1807
Discovered by: Humphry Davy
Frequently asked questions
What is the atomic number of Sodium?
Sodium has atomic number 11. Its symbol is Na and its atomic mass is 22.99 u.
What category of element is Sodium?
Sodium is classified as alkali metals. It sits in group 1, period 3 of the periodic table.
What block of the periodic table is Sodium in?
Sodium is in the s-block (group 1, period 3). Its highest-energy electrons occupy the s subshell — you can see this in its electron configuration, [Ne] 3s1.
What is Sodium used for?
Common uses of Sodium include: Table salt (with Cl), Street lamps, Soap.
When was Sodium discovered?
Sodium was discovered in 1807 by Humphry Davy.
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