19
K
Potassium
Alkali metal period 4 group 1 s-block discovered: 1807
As a chemical element
Properties of the atom — they do not depend on what substance it is part of.
- Atomic number
- 19
- Atomic mass
- 39.0983 a.m.u.
- Electron configuration
- [Ar]4s1
- Electronegativity
- 0.82 on the Pauling scale
- Atomic radius
- 275 pm
- Ionization energy
- 4.341 eV
- Electron affinity
- 0.501 eV
- Oxidation states
- +1
As a simple substance
Properties of the substance these atoms form under ordinary conditions.
- State at 25 °C
- Solid
- Melting point
- 336.53 K (63,38 °C)
- Boiling point
- 1032 K (758,85 °C)
- Density
- 0.89 g/cm³