Periodicity.

One might ask what is periodicity? The word periodicity has many meanings. Periodicity is defined as the occurrence of similar properties in elements having similar positions in the periodic table. Periodicity is found through certain periodic trends. There are four periodic trends found in the periodic table: atomic radius, ionization energy, electron affinity, and electronegativity.
The first periodic trend is atomic radius. Atomic radius is found in several ways. The radii of some atoms are determined by measuring the distance between like atoms that are joined together. There are other…