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Definition: periodic table


A list of all chemical elements known to mankind sorted by the number of protons they contain within the atom. As of 2021, there are 118 elements starting with hydrogen, which has one proton. The first 94 are found in nature, while the remaining are synthesized in a lab.

What's Periodic About It?
Periodicity is a chemistry term that refers to the behavior of the elements based on the number of protons in the atom. For the world at large, an "element table" makes more sense. See atom.