JEE Main 2025 · ChemistryMultiple choiceSingle correctEasyRecall

JEE Main 7 April 2025, Shift 1, Chemistry Q63

Question 63 of 75 in this shift, Chemistry question 13 of 25, Section A.

When a salt is treated with sodium hydroxide solution it gives gas X. On passing gas X through reagent Y a brown coloured precipitate is formed. X and Y respectively, are

(1)X = HCl and Y = $\mathrm{NH_4Cl}$
(2)X = $\mathrm{NH_4Cl}$ and Y = KOH
(3)X = $\mathrm{NH_3}$ and Y= HgO
(4)X = $\mathrm{NH_3}$ and Y = $\mathrm{K_2HgI_4}$ + KOHOfficial answer

Official answer

Option 4

NTA final key.

Chapter: Hydrogen
Topic: Cation Analysis
Idea tested: Group 0: Nessler's Reagent Complex Formula

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.