The two very common periodic trends are ionization energy and electronegativity.
Explanation:
The ionization energy refers to the energy being required to become an ion by either losing or by gaining the electron. It is the tendency to become an ion. This property has a trend of increasing when going left to right in the period of the periodic table.
Electronegativity denotes the ability of the atom to bond an electron with itself. And this shows the trend of decreasing down the row with increasing from left to the right across the period. Some other periodic trends are metallic character, atomic radius, electron affinity, and melting point.
