The element with atomic number 20 is Calcium (Ca). It is an alkaline earth metal, which means it is found in group 2 of the periodic table.
Calcium plays a vital role in various biological processes, including muscle contraction, blood clotting, and the formation of bones and teeth. It is essential for living organisms, particularly in the structure and function of cellular components.
In its pure form, calcium is a silvery-white metal that is soft enough to be cut with a knife. It reacts readily with water and air, which is why it is usually found in nature in compound forms, such as calcium carbonate (CaCO3) or calcium phosphate (Ca3(PO4)2).