Discuss Fajan's rules ?

Explanation

Fajan.s rule are as follows :
1 Smaller the size of cation, more will be the its polarizing power and more will be the covalent character of ionic bond. When the cation has smaller size, its density is high. It will have greater attraction for the electrons of the anion
For example the polarizing power of `L^(+)` is greater than the polarizing power of `Na^(+)`,
2 Larger the size of anion, higher will bhe its polarisability and more will be the covalent character of ionic bond. When the size is larger, the electron cloud is less tightly held by the molecule. the electropns cloud gets easily distorted.

For example : I can be easily polarized that `Cl^(-)`. So Lil more covalent that LiCl.
Similarly `AlCl_(3)` is covalent and `Alf_(3)` is ionic.