Nat Turner led a slave revolt several years before the Civil War. The revolt failed and he was killed. he is known for leading 2 uprises in Virginia in 1831 before getting caught.
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 abundant element in Earthâs crust.
a chemical element, atomic number 20, atomic weight 40.08. (See Appendix 6.) Calcium is the most abundant mineral in the body. In combination with phosphorus it forms calcium phosphate, the dense, hard material of the bones and teeth.