The Periodic Table of the Elements is an ingenious chart. It is a tool for understanding how each element relates to other elements and predicting how it will react to other elements etc. If you know the location of an element on the Periodic Table of the Elements, you know how many shells it has and how many it has, which tells you whether its a metal, nonmetal, or a metalloid or semimetal. a. Valence Electrons
b. mass number
c. neutrons
d. atomic mass