Atomic number 51
Antimony
Metalloid
Quick facts
- Atomic mass
- 121.76
- Group
- 15
- Period
- 5
- State (STP)
- solid
- Electronegativity
- 2.05
- Common ox. states
- -3, +3, +5
Properties
Electron configuration
[Kr] 4d¹⁰ 5s² 5p³
- Ionization energy
- 834.0 kJ/mol
- Electron affinity
- 103.0 kJ/mol
- Melting point
- 903.78 K (630.6 °C)
- Boiling point
- 1860.00 K (1586.8 °C)
How it bonds
Antimony continues the group-15 trend: 3 bonds + 1 lone pair (SbH₃, stibine), expanded-octet +5 in Sb₂O₅. Mostly used as a flame retardant additive (Sb₂O₃) in plastics and textiles.