Antimony (Sb) - Element 51 | Properties & Electron Configuration
What is Antimony?
Antimony (Sb) is element 51, a metalloid in period 5, group 15. Its electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p³.
| Atomic Number | 51 |
| Symbol | Sb |
| Atomic Mass | 121.76 u |
| Category | Metalloid |
| Period | 5 |
| Group | 15 |
| Block | p |
| Electron Configuration | 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p³ |
| Short Config | [Kr] 4d¹⁰ 5s² 5p³ |
| Electronegativity | 2.05 |
| Atomic Radius | 140 pm |
| Ionization Energy | 834 kJ/mol |
| Electron Affinity | 103 kJ/mol |
| Phase (STP) | Solid |
Electron Configuration
The full electron configuration of Antimony is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p³. In noble gas shorthand, this is written as [Kr] 4d¹⁰ 5s² 5p³.
Antimony is a p-block element in group 15, period 5.
Periodic Trends
Electronegativity: Antimony has a Pauling electronegativity of 2.05. Within group 15, electronegativity generally decreases down the group.
Atomic Radius: 140 pm. Across period 5, atomic radius generally decreases left to right as nuclear charge increases.
Ionization Energy: 834 kJ/mol. Ionization energy generally increases across a period and decreases down a group.
View all 118 elements with trend overlays for electronegativity, atomic radius, ionization energy, and electron affinity.
Explore Antimony on the Interactive Periodic TableRelated Topics
Nitrogen (N)
Properties of Nitrogen - same group as Antimony
Phosphorus (P)
Properties of Phosphorus - same group as Antimony
Arsenic (As)
Properties of Arsenic - same group as Antimony
Rubidium (Rb)
Properties of Rubidium - same period as Antimony
Strontium (Sr)
Properties of Strontium - same period as Antimony
Yttrium (Y)
Properties of Yttrium - same period as Antimony