JEE Main 2025 — Salt Analysis Question with Solution
From: JEE Main 2025 (Online) 2nd April Morning Shift
Question
Choose the correct tests with respective observations.
(A) (acidified with acetic acid) Chocolate brown precipitate.
(B) Prussian blue precipitate.
(C) , neutralised with White or bluish white precipitate.
(D) Blue precipitate.
(E) , neutralised with White precipitate.
Choose the correct answer from the options given below :
Choose an option
Show full solutionCorrect option: B
Step-by-step explanation
$2 \mathrm{CuSO}_4+\mathrm{K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right] \xrightarrow{\mathrm{CH}_3 \mathrm{COOH}}\begin{aligned} &\mathrm{Cu}_2\left[\mathrm{Fe}(\mathrm{CN})_6\right]+2 \mathrm{~K}_2 \mathrm{SO}_4\\ &\text { (Chocolate brown ppt.) } \end{aligned}$
$4 \mathrm{FeCl}_3+3 \mathrm{~K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right] \longrightarrow \begin{aligned} &\mathrm{Fe}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right]_3+12 \mathrm{KCl}\\ &\text { (Prussian Blue ppt.) } \end{aligned}$
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This is a previous-year question from JEE Main 2025, covering the Salt Analysis chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.