Question

In the brown ring complex $\left[Fe\right(H_{2}O{)}_{5}NO{]}^{2+}$.

• A. $NO$ transfers its electron to $F{e}^{2+}$ to give $F{e}^{+}$ and $N{O}^{+}$
• B. Magnetic moment of iron is $3.87$ BM
• C. The colour is due to charge transfer
• D. All of the above

Answer 1

Answer: (D)

All of the above

In the brown ring complex, $\left[Fe\right(H_{2}O{)}_{5}NO{]}^{2+}$, $NO$ exists as $N{O}^{+}$ and $Fe$ is in $+1$ oxidation state.
$F{e}^{+}$ have $3$ unpaired electrons and so, its magnetic moment is $\mu =\sqrt{n(n+2)}=3.87$ BM
The colour of this complex therefore, arises due to ligand to metal charge transfer.

Hence, all statements are correct.