Boron (B)

Boron is a chemical element with symbol B and atomic number 5. It is a low-abundance element in the Solar system and in the Earth's crust.

Atomic Number

5

Atomic Mass

10.81 u

Category

metalloid

Phase

solid

Density

2.34 g/cm³

Electron Shells

2, 3

Atomic Structure

Protons: 5 • Electrons: 5 • Neutrons: Varies by isotope

Electron Configuration: 1s² 2s² 2p¹

Discovery

1808 • Joseph Louis Gay-Lussac, Louis Jacques Thénard