+**Periodic Trend**
+Periodic trends are repeating patterns in the properties of chemical elements across the [Periodic Table](/wiki/periodic_table). These predictable changes arise from the regular increase in [Atomic Number](/wiki/atomic_number) and the organized filling of electron shells. Understanding them allows for the prediction of an element's chemical and physical behavior.
+## See also
+- [Electronegativity](/wiki/electronegativity)
+- [Ionization Energy](/wiki/ionization_energy)
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