Question

The $O.S.$ of $Fe$ in $N{a}_2\left[Fe\right(CN{)}_{5}NO]$ and $N{a}_4\left[Fe\right(CN{)}_{5}NOS]$ is:

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

Answer 1

The correct option is A $+2,+2$

${Na}_2\left[Fe{\left(CN\right)}_{5}NO\right]\Rightarrow {Na}^{+}{\left[Fe{\left(CN\right)}_{5}NO\right]}^{-2}$

$\therefore x-5+1=-2$

$\therefore x-4=-2$

$\therefore x=+2$

$\therefore$ oxidation state of $Fe$ is $+2$

${Na}_4\left[Fe{\left(CN\right)}_{5}NOS\right]\Rightarrow {Na}^{+}{\left[Fe{\left(CN\right)}_{5}NOS\right]}^{4-}$

$\therefore x-5+1=-2$

$\therefore x=+2$

The O.S of $Fe$ in both the molecules in $+2$.