Question

The oxidation state of Fe in $\left[Fe{\left(H_{2}O\right)}_{5}NO\right]{SO}_4$ is :

• A. $+1$
• B. $+2$
• C. $+3$
• D. $+4$

Answer 1

Answer: (A)

$+1$

$NO$ in brown ring complex has $+1$ oxidation state.

Let oxidation state of Fe be $x$.

Therefore, $x+5\left(0\right)+\left(1\right)+(-2)=0$ = $x+1-2=0$

$x=+1$

Hence, the oxidation state of iron in the brown ring complex is $+1$.

Thus option A is correct.