Periodic Table of Elements




Boron was first discovered by Sir Humphrey Davy, Joseph-Louis Gay-Lussac, Louis Jacques Thnard at 1808 in England, France.

Name: Boron
Symbol: B
Atomic number: 5
Atomic weight: 9.0122
State: solid
Group, period, block: 2, 2, s
Color: white-gray metallic
Classification: alkaline earth metal
Electron configuration: 2s2 2p1

Physical properties

Density: 2.46 g/cm-3
Melting point: 2349 K, 2076 C, 3769 F
Boiling point: 4200 K, 3927 C, 7101 F

Atomic properties

Oxidation states: 3, 2, 1[3]
Electronegativity: 2.04 (Pauling scale)
Ionization energies: 1st: 800.6 kJmol-1
Covalent radius: 843 pm
Van der Waals radius: 192 pm
  • B
  • Electron Configuration


There are two naturally occurring isotopes of boron exist, 10B and 11B.

About 80.1% of the boran in nature is 11B.

About 19.9% of the boran in nature is 10B.