Polarizable

[sarahtang4B]

Order these anions in order from least to most polarizable: I-, Cl-, S2-, P3-

Order these cations in order from least to most polarizing power: Li+, Ca2+, Cs+, Ba2+

and then which ion pairs would have bonds with greatest ionic and greatest covalent character and why?

[Chem_Mod]

Bigger anions are more polarizable because their electron cloud is larger and thus more easily distorted. Atomic size increases as you go down a column.

Conversely, smaller cations have stronger polarizing power because their electrons are more "condensed" and can thus distort other electron clouds. Use atomic size trends.

Greatest ionic character is between the species with the most polarizability/greatest polarizing power because the electron clouds are more distorted, creating dipole moments. Greatest covalent character is between species with the least polarizability/least polarizing power.

[Jasmine Reddy DIS 1E]

Greatest ionic character is between the species with the most polarizability/greatest polarizing power because the electron clouds are more distorted, creating dipole moments. Greatest covalent character is between species with the least polarizability/least polarizing power.

In my notes, I wrote down that higher polarizability and higher polarizing power means greater covalent character. Is this incorrect?


I also thought that ionic character refers to unequal sharing of electrons in a polar covalent bond due to differences in electronegativity, and has nothing to do with polarizability and polarizing power.

[sarahtang4B]

So then would Cl- and Cs+ have greatest ionic character?

[Chem_Mod]

No, Cs+ does not have the highest polarizing power. Li+ and the ion with the more polarizability, I- would form bonds with the most ionic character.