How does the polarizing power of cations affect the covalent character imparted into the ionic bond ?

Explanation

Greater the polarization effect, greater will be covalent character imported into the ionic bond.
The general trend in the polarizing power of cations is `Li^(+) gt Na^(+) gt K^(+) gt Rb^(+) gt Cs^(+)`
`:.` Their covalnet charter : `LiCl gt NaCl gt KCl gt RbCl gt CsCl`