Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and …

Jan 9, 2026 · calcium (Ca), chemical element, one of the alkaline-earth metals of Group 2 (IIa) of the periodic table. It is the most abundant metallic element in the human body and the fifth most …

Calcium was named after the Latin term calx meaning lime, and is a reactive silvery metallic element found in Group 2 of the periodic table. It was first isolated in 1808 in England when Sir Humphry …

Calcium is an important element of the periodic table in biology, and medicine. Learn about calcium compounds, properties and uses, history, fun facts, and more!

The chemical element calcium is classed as an alkali earth metal. It was discovered in 1808 by Sir Humphry Davy.

Calcium, a metallic element, is fifth in abundance in the earth's crust, of which it forms more than 3%. It is an essential constituent of leaves, bones, teeth, and shells.

Calcium was known as early as the first century when the Ancient Romans prepared lime as calcium oxide. Calcium was first isolated by Sir Humphry Davy in 1808 when he electrolyzed a mixture of …

Calcium is an alkaline earth metal. The alkaline earth metals make up Group 2 (IIA) of the periodic table, a chart that shows how the elements are related. They include beryllium, magnesium, strontium, …

Apatite is the fluorophosphate or chlorophosphate of calcium. The metal has a silvery color, is rather hard, and is prepared by electrolysis of fused chloride and calcium fluoride (to lower the melting point).

Jun 5, 2015 · Natural calcium is comprised of six isotopes: 40 Ca, 42 Ca, 43 Ca, 44 Ca, 46 Ca, and 48 Ca. Five stable and nineteen radioactive isotopes exist ranging from 34 Ca to 57 Ca. Calcium-40 is a …