Question

In which of the following compounds are all the bond lengths equal?

• A. $PC{l}_5$
• B. $S{F}_6$
• C. $Cl{O}_4^{-}$
• D. $I{F}_7$

Answer 1

Answer: (B), (C)

The correct options are
B $S{F}_6$
C $Cl{O}_4^{-}$

$PC{l}_5$ has $s{p}^{3}d$ hybridisation and trigonal bipyramidal geometry in which axial bonds are longer than equatorial bonds.
$S{F}_6$ has $s{p}^3{d}^2$ hybridisation and octahedral geometry. So, all the bond lengths will be same.
$Cl{O}_4^{-}$ has a tetrahedral geometry. Here, resonance plays an important role because of which all the bonds are identical.
$I{F}_7$ has $s{p}^3{d}^3$ hybridisation and a pentagonal bipyramidal geometry in which equatorial bonds are longer than the axial bonds.