Alkali metal

Potassium

Potassium (K) has atomic number 19. PubChem classifies it as alkali metal.

Atomic number

19

Symbol

K

Atomic weight (source value)

39.0983

Electron configuration

[Ar]4s1

Standard state

Solid

Electronegativity (Pauling)

0.82

Melting point (K)

336.53

Boiling point (K)

1032

Density (g/cm³)

0.89

Oxidation states

+1

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.