Question

Which of the following metal halide has the highest ionic character?
(Here, $M$ is monovalent metal)

• A. $MI$
• B. $MCl$
• C. $MBr$
• D. $MF$

Answer 1

The correct option is D $MF$

According to Fajan's rule, as the size of anion increase its ionic character decrease. Since the size of $F^{-}$ is the lowest among halides hence $MF$ has the highest ionic character.
The order of ionic charcter among metal halides is:
$MF>MCl>MBr>MI$