Which among the following halogens combines readily with metals to form metal halides with highest ionic…
Which among the following halogens combines readily with metals to form metal halides with highest ionic character?
Chlorine
Bromine
Iodine
Fluorine
Solution
Ionic character of metal halides decreases in the order $\mathrm{MF}>\mathrm{MCl}>\mathrm{MBr}>\mathrm{MI}$, where, $\mathrm{M}$ is a monovalent metal. Smaller the size of anion, greater is the ionic character (Fajan's rule). Therefore, fluorine forms metal halides with highest ionic character.