The Periodic Table The periodic table is known as the most important tool in a chemical laboratory.The elements in the periodic table are classified into groups or families. The periodic table provides an easy way to show the divission of the elements into acid-forming and base-forming types.It is also a universal table. The periodic table is filled whith many virtues in which I will explain some in the following paragraphs. Elements are classified into families.Such as the halogen or the nitrogen family. This was first done in 1869 by the Russian chemist Dmitri Mendeleev. All elements in the same vertical row have similar chemical properties. This indicates that