Question

When both $N\text{and}S$ are present in an organic compound, what colour does the sodium extract with $FeC{l}_3$ give?

• A. Green
• B. Blue
• C. Yellow
• D. Red

Answer 1

The correct option is D Red

Sodium fusion extract is used to detect the presence of elements like $S,N,Cl,Br\text{and}I$
If both $N\text{and}S$ are present in organic compound then oragnic compound reacts with sodium fusion extract as follows:
$Na+S+C+N\to NaSCN$
This thiocyanate, $SC{N}^{-}$ reacts with $F{e}^{3+}$ to give a blood red colouration due to formation of $\left[Fe\right(SCN){]}^{2+}$.
$F{e}^{3+}+SC{N}^{-}\to \left[Fe\right(SCN){]}^{2+}$
(Red)
Hence, option d is correct.