PERIODIC ELEMENT
Ca (Calcium)

 



Atomic number : 20
Atomic mass : 40.08 g.mol-1
Electronegativity according to Pauling : 1.0
Density : 1.6 g.cm-3 at 20 °C
Melting point : 840 °C
Boiling point : 1484 °C
Vanderwaals radius : 0.197 nm
Ionic radius : 0.099 nm
Isotopes : 10
Electronic shell : [Ar] 4s2
Energy of first ionisation : 589.6 KJ.mol-1
Energy of second ionisation : 1145 KJ.mol-1
Standard potential : - 2.87 V
Discovered by : Sir Humphrey Davy in 1808
 
Atomic Structure Uses (life forms for bones and shells)