Question

arrange the following in increasing order of ionic character LiI, LiCl, LiBr. according to fajan's rule.

Answer 1

Fajans rule states that the polarising power is directly proportional to the radius of anion. hence the bigger the anion the more covalent it is.

Hence LiCl is the most ionic whereas LiI is most covalent.

Therefore increasing order of ionic character

LiI , LiBr, LiCl

Answer 2

Answer: The order of ionic character follows the order: $LiCl>LiBr>LiI$

Explanation:

Fajan's rule determines the ionic or covalent character of compounds.

According to fajan's rule, compounds in which cations have small positive charge means that the cation is large and anions which are small are more likely to be ionic and if the cation has large positive charge which means that the cation is small, and the anion would be large, then the compound is most likely to be covalent.

In the given compounds, LiCl , LiBr and LiI.

The cation is the same and has small positive charge which means that the cation is large. So, to form an ionic compound, anion must be small.

In between chlorine, bromine and iodine, the size of chlorine is small so it will form a small anion. Hence, LiCl is the most ionic amongst given compounds.

Hence, the order of ionic character follows the order: $LiCl>LiBr>LiI$