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51Sb

Element 51

Antimony

Metalloids

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

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 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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