Metalloid

Boron

Boron (B) has atomic number 5. PubChem classifies it as metalloid.

Atomic number

5

Symbol

B

Atomic weight (source value)

10.81

Electron configuration

[He]2s2 2p1

Standard state

Solid

Electronegativity (Pauling)

2.04

Melting point (K)

2348

Boiling point (K)

4273

Density (g/cm³)

2.37

Oxidation states

+3

Understanding this entry

Atomic number is the number of protons in the nucleus. Properties are reference values and may depend on conditions and measurement conventions. An atomic weight is not the mass of every isotope. For elements without a standard atomic weight, a source may report an isotope mass number. Blank source values are shown as unavailable rather than estimated.

Further reading and reference: NIH PubChem source dataset ↗. Values and educational summaries are not a substitute for specialised advice.