Q. Which of the following complex formation indicates presence of sulphur in the organic compound when sodium nitroprusside is added to sodium extract of the compound?
A) $Fe_{4}\left\lbrack Fe(CN)_{6} \right\rbrack_{3}$
B) $Na_{2}\left\lbrack Fe(NO)(CN)_{5} \right\rbrack$
C) $Fe_{4}(CNS)_{3}$
D) $Na_{4}\left\lbrack Fe(CN)_{5}NOS \right\rbrack$
Explanation
(d)
The formation of sodium thionitroprusside (blue) shows the presence of sulphur.
$Na_{2}S\ + \ \ \ Na_{2}\left\lbrack Fe(NO)(CN)_{5} \right\rbrack \longrightarrow \ \ \ \ \ Na_{4}\left\lbrack Fe(CN)_{5}NOS \right\rbrack$
Sodium sodium nitroprusside sodium thionitroprusside purple
extract
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.