Match List I with List II Choose the correct answer from the options given below:
- A-III, B-I, C-IV, D-II
- A-III, B-IV, C-I, D-II
- A-III, B-II, C-IV, D-I
- A-III, B-I, C-II, D-IV
Answer
(2) A-III, B-IV, C-I, D-II
Solution
A. Borax bead: Na2B4O7 2NaBO2 + B2O3
B2O3 + metal oxide gives the coloured metaborate M(BO2)2, so A-III
B. Charcoal cavity: fused with Na2CO3, MCO3 gives MO, which carbon reduces to M, so B-IV
C. Cobalt nitrate: MO and CoO give the coloured CoO MO (e.g. Thenard's blue for Al), so C-I
D. Flame test: conc. HCl gives the volatile MCl2, whose M2+ colours the flame, so D-II
Hence A-III, B-IV, C-I, D-II.
Answer: (2)