General Organic Chemistry Question 23
Question 23 - 2024 (29 Jan Shift 1)
Appearance of blood red colour, on treatment of the sodium fusion extract of an organic compound with $\mathrm{FeSO}{4}$ in presence of concentrated $\mathrm{H}{2} \mathrm{SO}_{4}$ indicates the presence of element/s
(1) $\mathrm{Br}$
(2) $\mathrm{N}$
(3) $\mathrm{N}$ and $\mathrm{S}$
(4) $\mathrm{S}$
Show Answer
Answer (3)
Solution
Formula: Lead acetate test
$$ \mathrm{Fe}^{2+} \xrightarrow[\text { Conc. } \mathrm{H}{2} \mathrm{SO}{4}]{\mathrm{H}^{+}} \mathrm{Fe}^{+3} $$
$\mathrm{Fe}^{+3} \xrightarrow{-\mathrm{SCN}} \mathrm{Fe}(\mathrm{SCN})_{3}($ blood red colour $)$
Appearance of blood red colour indicates presence of both nitrogen and sulphur.
