19
K
39.098
Potassium
Element 19 · 39.098 u · s-block
alkali metal
A soft, silvery metal that reacts violently with water. Essential for nerve function and found in bananas.
Phase (STP)
Solid
Melting Point
63.5 °C
Boiling Point
759 °C
Density
0.862 g/cm³
Electronegativity
0.82
Atomic Radius
220 pm
Ionization Energy
419 kJ/mol
Electron Affinity
48 kJ/mol
Discovered
1807 · Humphry Davy
Electron Configuration
[Ar] 4s1
Electron Orbitals
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