Question

In test of $N{O}_3^{-}$ ion, the dark brown ring complex is formed, which is true of this complex?

• A. The colour is due to charge transfer spectra
• B. Iron and $NO$ both have $+1$ charge
• C. The complex species can be represented as $\left[F{e}^1\right(H_{2}O{)}_{5}NO{]}^{2+}$
• D. Iron has $+2$ oxidation state and $NO$ is neutral

Answer 1

Answer: (A), (B), (C)

The complex species can be represented as $\left[F{e}^1\right(H_{2}O{)}_{5}NO{]}^{2+}$
The colour is due to charge transfer spectra
Iron and $NO$ both have $+1$ charge

When nitrate ion reacts with conc. $H_{2}s{O}_4$ in presence of $FeS{O}_4$, a brown ring complex $\left[Fe\right(H_{2}O{)}_{5}NO]S{O}_4$ is obtained.
The charge transfer spectra result in brown colour complex.
Iron and NO both have $+1$ charge.