Covalent Character

[Celeste 1I]

How do you use polarizability and polarizing power to determine which molecule has a higher covalent character. Like between CaS and CaO?

[AvaGordon_4F]

So covalent character is between atoms closer together on the table (that are most willing to SHARE their electron), whereas ionic character is between elements further apart (that are more willing to entirely donate their electrons). Between O and S, which are in the same group, but different periods, their size (and therefore the amount of pull the nucleus exerts on valence electrons) will dictate which has the more covalent character