Element 51
Antimony
Metalloids
Antimony (Sb) is in the p-block of the periodic table — group 15, period 5.
Antimony is a chemical element with symbol Sb (from Latin:stibium) and atomic number 51.
Key data
- Atomic number
- 51
- Atomic mass
- 121.760 u
- Group / Period
- 15 / 5
- Block
- p-block
- Phase at STP
- Solid
- Density
- 6.697 g/cm³
- Melting point
- 630.6 °C
- Boiling point
- 1634.8 °C
- Electron configuration
- [Kr] 4d10 5s2 5p3
Periodic table block
Antimony is in the p-block (group 15, period 5). Elements land in the p-block when their highest-energy electrons fill a p subshell — this region holds most nonmetals, the metalloids, and the metals on the right of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Flame retardants
- •Lead-acid batteries
- •Cosmetics history
Discovery
Year: Known since antiquity
Discovered by: unknown, before 3000 BC
Frequently asked questions
What is the atomic number of Antimony?
Antimony has atomic number 51. Its symbol is Sb and its atomic mass is 121.76 u.
What category of element is Antimony?
Antimony is classified as metalloids. It sits in group 15, period 5 of the periodic table.
What block of the periodic table is Antimony in?
Antimony is in the p-block (group 15, period 5). Its highest-energy electrons occupy the p subshell — you can see this in its electron configuration, [Kr] 4d10 5s2 5p3.
What is Antimony used for?
Common uses of Antimony include: Flame retardants, Lead-acid batteries, Cosmetics history.
When was Antimony discovered?
Antimony has been known since antiquity.
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