Question

The common features among the species $C{N}^{-},CO$ and $N{O}^{+}$ are

• A. bond order three and iso-electronic
• B. bond order three and weak-field ligands
• C. bond order two and $\pi$ -acceptor
• D. iso-electronic and weak-field ligands

Answer 1

Answer: (A)

$C{N}^{-}:14$ electrons (carbon - $6$, nitrogen - $7$, add $1$ for negative charge) and bond order is $3$ because of three covalent bonds between the atoms.
$CO:14$ (carbon $-6$, oxygen $-8$ ) and bond order is $3$ because of three covalent bonds between the atoms..
$N{O}^{+}:14$ (nitrogen $-7$, oxygen - $8$ and subtract $1$ for positive charge) and bond order is $3$ because of three covalent bonds between the atoms.
$14$ electrons system like $N_2$ will have diamagnetic character.