Question

Why most metal fluorides are ionic than metal chlorides?

Answer 1

Metal fluorides are more ionic than metal chlorides because -

Fluorine is smaller in size than cl

Electronegativity of Fluorine is higher than chlorine

Since the ionic character of elements increases with the increasing electronegativity

This leads to an increased ionic character of F and it has a lesser tendency to form a covalent bond.

Answer 2

The ionic character depends mainly on the size and electronegativity of the atoms forming the bond. Fluoride ion is much smaller than chloride ion as well as more electronegative than chloride ion. Both these reasons ultimately make the respective metal florides more ionic than metal chlorides.