Atomic number 11
Sodium
Alkali metal
Quick facts
- Atomic mass
- 22.990
- Group
- 1
- Period
- 3
- State (STP)
- solid
- Electronegativity
- 0.93
- Common ox. states
- +1
Properties
Electron configuration
[Ne] 3s¹
- Ionization energy
- 495.8 kJ/mol
- Electron affinity
- 52.8 kJ/mol
- Melting point
- 370.94 K (97.8 °C)
- Boiling point
- 1156.09 K (882.9 °C)
How it bonds
Sodium loses its single 3s electron easily to form Na⁺. It is the textbook alkali metal — bonds ionically with halogens (NaCl, NaF), oxide-formers (Na₂O), and acids (NaOH). The +1 ion is so stable in water that you almost never see anything else.
Where you meet it
- Periodic Quest challengeunlock card