Barium Barium Barium is a chemical element with symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. Its hydroxide, known in pre-modern times as baryta, does not occur as a mineral, but can be prepared by heating barium carbonate. The most common naturally occurring minerals of barium are barite (now called baryte) (barium sulfate, BaSO) and witherite (barium carbonate, BaCO), both insoluble in water. The name "barium" originates from the alchemical derivative
Chemical compound Chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) composed of atoms from more than one element held together by chemical bonds. A chemical element bonded to an identical chemical element is not a chemical compound since only one element, not two different elements, is involved. There are four types of compounds, depending on how the constituent atoms are held together: A chemical formula is a way of expressing information about the proportions of atoms that constitute a particular chemical compound, using the standard abbreviations for the chemical elements, and subscripts to