Which of the following species is not expected to be a ligand?

Options

A. NO
B. `NH_(4)^(+)`
C. `NH_(2)CH_(2)CH_(2)NH_(2)`
D. CO

Answer

1

Explanation

Ligand must donate a pair of electrons of loosely held electron pair to metal and form a M-L bond.
`e.g : overset(..)(N) = O, overset(..)(N)H_(2)CH_(2)CH_(2)overset(..)(N)H_(2), : CO`
Among all `NH_(4)^(+)` does not have any pair of electrons.
Hence `NH_(4)^(+)` is not a ligand.