Question

Polarization is an important phenomenon which is helpful in determination of covalent nature of compound. With the help of Fajan's rule one can easily predict the nature of compound.
Which of the following possess the least covalent character?

• A. $LiCl$
• B. $NaCl$
• C. $KCl$
• D. $CsCl$

Answer 1

The correct option is D $CsCl$

The anion is moderately large and polarizable. The charge density or rather the polarizing power of the cation
decides the covalent character.

Covalent character decreases as:
$LiCl>NaCl>KCl>RbCl>CsCl$