Properties

Atomic Number	20
CAS Registry Number	7440-70-2
Chemical Symbol	Ca

History

The atomic number is 20 and the chemical symbol is Ca. The name derives from the Latin calx for lime (CaO) or limestone (CaCO3) in which it was found. It was first isolated by the British chemist Humphry Davy in 1808 with help from the Swedish chemist Jons Jacob Berzelius and the Swedish court physician M.M. of Pontin who had prepared calcium amalgam.

Holden, Norman E., (2004). History of the origin of the chemical elements and their discoverers. National Nuclear Data Center. Retrieved from http://www.nndc.bnl.gov/content/elements.html