Calcium (Ca)

Calcium (Ca)

Atomic Number: 20
Atomic Weight: 40.08
Melting Point: 839
Boiling Point: 1484
Specific Gravity: 1.55
Valences: 2

In 1808, Calcium was discovered by Davy. Calcium is 5th in abundance in the earth's crust and occurs naturally in limestone and gypsum. It is essential in bones, shells, and teeth. Calcium, mixed with sand, hardens into mortar and plaster. Calcium Oxide, also known as lime, was prepared by the Romans back in the 1st Century under the name calx. [LM] {RW}