Periodic Table of Elements




Compounds of sodium like salt have been known since ancient times. Pure sodium was discovered by Sir Humpry Davy in 1807. He isolated pure sodium by using the electrolysis of caustic soda.

Name: Sodium
Symbol: Na
Atomic number: 11
Atomic weight: 22.990
State: solid
Group, period, block: 1, 3, s
Color: silvery white metallic
Classification: alkali metal
Electron configuration: 3s1

Physical properties

Density: 0.968 g.m-3
Melting point: 370.87 K, 97.72 C, 207.9 F
Boiling point: 1156 K, 883 C, 1621 F

Atomic properties

Oxidation states: +1, -1
Electronegativity: 0.93 (Pauling scale)
Ionization energies: 1st: 495.8 kJmol-1
Covalent radius: 1669 pm
Van der Waals radius: 227 pm
  • Na
  • Electron Configuration


There is one naturally occurring isotope of sodium exist, 23Na.