Question

Select the number of species having bond with fractional bond order (Indicated bond)
$N_3^{-},C{O}_3^{2-},Cl{O}_3,Cl{O}_3^{-},O_3,C{O}_2,B{F}_3,A{l}_{2}C{l}_6,C{H}_{3}COOH$ ( $C-O$ bond)

Answer 1

Answer: 5

Molecule or ions that have resonance structure i.e. fractional bond order is possible $C{O}_3^{2-},Cl{O}_3^{-},O_3,B{F}_3,C{H}_{3}COOH$ ( $C-O$ bond)
Fractional bond order
$N_3^{-}$

$C{O}_3^{2-}$

$B.O.=\frac{4}{3}=1.33$
$Cl{O}_3$

$B.O.=2$
$Cl{O}_3^{-}$

$B.O.=\frac{5}{3}=1.66$
$O_3$

$B.O.=\frac{3}{2}=1.5$
$C{O}_2$
$O=C=O$
$B.O.=2$
$B{F}_3$

$B.O=1.33$
$A{l}_{2}C{l}_6$

$B.O.=1$
$C{H}_{3}COOH$ ( $C-O$ bond)