The number of lone pairs in ${\mathrm{XeF}}_2,{\mathrm{XeF}}_4$ and ${\mathrm{XeF}}_6$ are respectively

$\mathrm{Xe}$ has 8 valence electrons.

• In ${\mathrm{XeF}}_2$, it has a linear structure. It has two $\mathrm{Xe}-\mathrm{F}$ bonds lying linear to each other.

                         The number of lone pairs are 3.

• $In{\mathrm{XeF}}_4$, it has a square planar structure. The four $\mathrm{Xe}-\mathrm{F}$ bonds are perpendicular to each other.

                      The number of lone pairs are 2. 

• $In{\mathrm{XeF}}_6$ it has distorted octahedral structure .It has 6 bond pairs and 1 lone pair

Hence, the number of lone pairs in ${\mathrm{XeF}}_2,{\mathrm{XeF}}_4$ and ${\mathrm{XeF}}_6$ are 3, 2 and 1.