The formula H₂O shows that water is made from two atoms of hydrogen (H) bonded to one atom of oxygen (O). Katie: Time for some science. And today it's a chemistry classic, the periodic table.

The Rules for Chemical Symbols These rules help in identifying and writing chemical symbols consistently across all elements. The symbol serves as a shorthand notation for each element's name in ...

The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...