Arrange the bonds in order of increasing ionic character in the molecules. LiF , K 2 O , N 2 , SO 2 and ClF…

The ionic character in a molecule is dependent upon the electronegativity difference between the constituting atoms. The greater the difference, the greater will be the ionic character of the molecule.

${\mathrm{N}}_2<{\mathrm{SO}}_2<{\mathrm{ClF}}_3<{\mathrm{K}}_2\mathrm{O}<\mathrm{LiF}$

The Ionic character depends upon the difference in electronegativity (bond polarity).

${\mathrm{N}}_2$ is a covalent molecule & the difference in electrongegativities are:
|X_S – X₀| $=$ $1.0$
|X_Cl – X_F| $=1.0$
|X_K – X₀| $=2.6$
|X_Li – X_F| $=3.5$