Antimony

Metalloid · atomic number 51

51121.7601SbAntimonySolidMetalloid

Antimony is a chemical element with symbol Sb (from Latin:stibium) and atomic number 51. A lustrous gray metalloid, it is found in nature mainly as the sulfide mineral stibnite (Sb2S3). Antimony compounds have been known since ancient times and were used for cosmetics; metallic antimony was also known, but it was erroneously identified as lead upon its discovery.

Properties of Antimony

Element category	Metalloid
Atomic number	51
Atomic mass	121.7601 u
Phase at STP	Solid
Group	15
Period	5
Block	p
Electron configuration	[Kr] 4d10 5s2 5p3
Electrons per shell	2, 8, 18, 18, 5
Electronegativity (Pauling)	2.05
Melting point	903.78 K (631 °C)
Boiling point	1908 K (1635 °C)
Density	6.697 g/cm3
Discovered by	unknown, before 3000 BC

← Tin · Periodic table · Tellurium → Te

About the metalloid group

In-between elements that behave as semiconductors: silicon, germanium and boron underpin electronics, glass and solar cells.

Data: Periodic-Table-JSON (CC BY-SA 3.0) · stored statically on our server. https://en.wikipedia.org/wiki/Antimony

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