What is the electronegativity difference that characterizes a Polar Ionic Bond?

A polar ionic bond is characterized by a significant electronegativity difference between the two atoms involved in the bond, typically greater than 1.7. This substantial difference indicates that one atom has a strong tendency to attract electrons compared to the other, leading to an unequal sharing of electrons. In the context of bonding, when this electronegativity difference exceeds 1.7, it suggests that the bond will exhibit ionic character, where one atom effectively donates electrons, and the other accepts them, resulting in the formation of ions.

The range of electronegativity differences allows us to categorize bonds as nonpolar covalent, polar covalent, or ionic. A difference of less than 0.4 corresponds to a nonpolar covalent bond, where electrons are shared equally. A difference between 0.4 and 1.7 denotes a polar covalent bond, characterized by unequal sharing but not complete transfer of electrons. However, once the difference is greater than 1.7, the bond formation shifts towards ionic character, affirming the nature of the polar ionic bond.