Learn

Friday, 9 October

JEE Main 2024 · ChemistryMultiple choiceMatch the listMediumRecall

JEE Main 8 April 2024, Shift 1, Chemistry Q72

Question 72 of 90 in this shift, Chemistry question 12 of 30, Section A.

Match List I with List II LIST I (Name of the test): A. Borax bead test; B. Charcoal cavity test; C. Cobalt nitrate test; D. Flame test LIST II (Reaction sequence involved) [M is metal]: I. MCO3→MO→+ΔCo(NO3)2CoO⋅MO\mathrm{MCO_3\rightarrow MO\xrightarrow[+\Delta]{Co(NO_3)_2}CoO\cdot MO} II. MCO3→MCl2→M2+\mathrm{MCO_3\rightarrow MCl_2\rightarrow M^{2+}} III. MSO4→ΔNa2B4O7M(BO2)2→MBO2→M\mathrm{MSO_4\xrightarrow[\Delta]{Na_2B_4O_7}M(BO_2)_2\rightarrow MBO_2\rightarrow M} IV. MSO4→ΔNa2CO3MCO3→MO→M\mathrm{MSO_4\xrightarrow[\Delta]{Na_2CO_3}MCO_3\rightarrow MO\rightarrow M} Choose the correct answer from the options given below:
  1. (1)A-III, B-I, C-II, D-IV
  2. (2)A-III, B-II, C-IV, D-I
  3. (3)A-III, B-I, C-IV, D-II
  4. (4)A-III, B-IV, C-I, D-IIOfficial answer

Official answer

Option 4

NTA final key.

Same idea in other shifts

Asked 2× in all
  1. 2 Apr 2026, Shift 1 · Q70A salt with few drops of conc. HCl gives apple green colour in flame test. The group precipitate of the salt is dissolved in acetic acid…MediumSingle correct

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.