20
Ca
40.078
Calcium
Element 20 · 40.078 u · s-block
alkaline earth
The most abundant metal in the human body. Essential for bones, teeth, and muscle contraction.
Phase (STP)
Solid
Melting Point
842 °C
Boiling Point
1484 °C
Density
1.55 g/cm³
Electronegativity
1.0
Atomic Radius
180 pm
Ionization Energy
590 kJ/mol
Electron Affinity
2 kJ/mol
Discovered
1808 · Humphry Davy
Electron Configuration
[Ar] 4s2
Electron Orbitals
Drag to rotate · Pinch to zoom