Anomalous Behavior of First Element in P Block

The first element of each group in the p-block shows anomalous behavior due to several reasons:

• Small Size: The first element in each group is smaller in size compared to the other elements. For example, boron is much smaller than aluminum.
• High Electronegativity: The first element has higher electronegativity compared to others in the group. For instance, fluorine has higher electronegativity than chlorine.
• Absence of D-Orbitals: The first element does not have d-orbitals in its valence shell, which affects its bonding and chemical properties. For example, carbon lacks d-orbitals unlike silicon.
• Hydrogen Bonding: The first elements like nitrogen, oxygen, and fluorine can form hydrogen bonds, which significantly affect their properties.
• Greater Ionization Energy: The first element has higher ionization energy compared to others, making it less reactive. For instance, nitrogen has higher ionization energy than phosphorus.