Boron

Metalloid · atomic number 5

510.81BBoronSolidMetalloid

Boron is a metalloid chemical element with symbol B and atomic number 5. Produced entirely by cosmic ray spallation and supernovae and not by stellar nucleosynthesis, it is a low-abundance element in both the Solar system and the Earth's crust. Boron is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals.

Properties of Boron

Element category	Metalloid
Atomic number	5
Atomic mass	10.81 u
Phase at STP	Solid
Group	13
Period	2
Block	p
Electron configuration	[He] 2s2 2p1
Electrons per shell	2, 3
Electronegativity (Pauling)	2.04
Melting point	2349 K (2076 °C)
Boiling point	4200 K (3927 °C)
Density	2.08 g/cm3
Discovered by	Joseph Louis Gay-Lussac

← Beryllium · Periodic table · Carbon → C

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/Boron

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11 elements: Elements that readily gain or share electrons — the building blocks of water, air, living tissue and most organic chemistry.

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6 elements: Full outer electron shells make these gases almost inert: they barely react, glow in discharge lamps and are used to create unreactive atmospheres.

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🧪 Metalloid

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

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