How does an element’s atomic number determine its position on the periodic table?

The atomic number of a chemical element is defined as the number of protons found in the nucleus of its atoms. This value serves as the fundamental basis for organizing the periodic table.123

Elements are arranged on the table in order of increasing atomic number. Because the number of protons in a neutral atom is equal to the number of electrons, the atomic number also dictates the electronic structure of the atom. This arrangement is significant because the chemical properties of elements are determined by their electron configurations.132

When elements are ordered by their atomic numbers, a recurring pattern known as the periodic law emerges, where elements in the same vertical column, or group, exhibit similar chemical properties due to analogous valence electron configurations. Consequently, the atomic number acts as the primary identifier that determines an element's specific position within the periodic system.4352