Q. Red colour complex ion formed on adding $FeCl_{3}$ to sodium extract when N and S both are present in organic compound is
A) $\left\lbrack Fe(CN)_{6} \right\rbrack^{4 -}$
B) $\left\lbrack Fe(CNS) \right\rbrack^{2 +}$
C) $\left\lbrack Fe(CNS)_{2} \right\rbrack^{+}$
D) $\left\lbrack Fe(CN)_{6} \right\rbrack^{3 -}$
Explanation
(b)
When N and S both are present in the organic compound, then a red colour complex ion of $\left\lbrack Fe(CNS) \right\rbrack^{2 +}$ is formed on adding $FeCl_{3}$ to sodium extract
$NaCNS + FeCl_{3} \rightarrow \left\lbrack Fe(SCN) \right\rbrack Cl_{2} + NaCl$
blood red colour
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.