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5B

Element 5

Boron

Metalloids

Boron is a metalloid chemical element with symbol B and atomic number 5.

Key data

Atomic number
5
Atomic mass
10.810 u
Group / Period
13 / 2
Block
p-block
Phase at STP
Solid
Density
2.08 g/cm³
Melting point
2075.8 °C
Boiling point
3926.8 °C
Electron configuration
[He] 2s2 2p1

Common uses

  • Pyrex glass
  • Detergents (borax)
  • Semiconductor doping

Discovery

Year: 1808

Discovered by: Joseph Louis Gay-Lussac

Frequently asked questions

What is the atomic number of Boron?

Boron has atomic number 5. Its symbol is B and its atomic mass is 10.81 u.

What category of element is Boron?

Boron is classified as metalloids. It sits in group 13, period 2 of the periodic table.

What is Boron used for?

Common uses of Boron include: Pyrex glass, Detergents (borax), Semiconductor doping.

When was Boron discovered?

Boron was discovered in 1808 by Joseph Louis Gay-Lussac.

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