Barium is a metal in group IIA of the periodic table with atomic number 56, an atomic weight of 137.34, and a density of 3.5 Mg/m 3. Its melting point is 714 C, and it boils at 1640 C. The electronic ...

These elements are building blocks of matter and everything around us is made up of them. There are 118 elements in the periodic table, each with a unique symbol and atomic number.