Question

Consider the following experiments and answer the questions at the end of it
(A) When $Fe(CN{)}_2$ solution is treated with KCN solution, species formed, no longer, gives tests ofFe ${}^{2+}$ and $C{N}^{-}$
(B) When $K_{2}S{O}_4$ solution is treated with $A{l}_2{\left(S{O}_4\right)}_3$ solution, species formed give tests of $K^{+},A{l}^{3+}$ and $S{O}_4^{2-}$
Species formed in experiment $A$ does not give test ofFe ${}^{2+}$ and $CN{}^{-}$. It is due to formation of

• A. $K_2\left[Fe(CN{)}_4\right]$
• B. $K_2\left[Fe(CN{)}_5\right]$
• C. $K_3\left[Fe(CN{)}_6\right]$
• D. $K_4\left[Fe(CN{)}_6\right]$

Answer 1

Answer: (D)

Correct answer is (d) $K_4\left[Fe(CN{)}_6\right]$