Final answer:
The periodic table is a cornerstone of chemistry as it organizes all elements based on their chemical properties and provides additional data. Elements are listed in order of atomic number.
Step-by-step explanation:
The periodic table is one of the cornerstones of chemistry because it organizes all of the known elements on the basis of their chemical properties. Most periodic tables provide additional data (such as atomic mass) in a box that contains each element's symbol. The elements are listed in order of atomic number.