Question

Match List-I with List-II.

List-I (Name of the test)	List-II (Reaction sequence involved) [M is metal]
(A) Borax bead test	I
(B) Charcoal cavity test	II
(C) Cobalt nitrate test	III
(D) Flame test	IV

Choose the correct answer from the options given below:

• A. A-III, B-I, C-IV, D-II
• B. A-III, B-II, C-IV, D-I
• C. A-III, B-I, C-II, D-IV
• D. A-III, B-IV, C-I, D-II

Answer 1

The Correct Option is D

To solve the question, we need to correctly match each test from List-I with the corresponding reaction sequence from List-II.

1. Borax Bead Test:
   This test is used to identify certain metals. The equation involved is:This sequence involves the use of Na₂B₄O₇ in the reaction. Hence, (A) Borax bead test matches with III.
2. Charcoal Cavity Test:
   This test helps to identify metal salts that, when reduced, leave a characteristic residue in the cavity. The equation is:This involves reactions happening on charcoal and hence, (B) Charcoal cavity test matches with IV.
3. Cobalt Nitrate Test:
   This is a test for the detection of compounds that produce cobalt or its oxides. The relevant equation is:The sequence involves cobalt nitrate, so (C) Cobalt nitrate test matches with I.
4. Flame Test:
   This test is used to detect the presence of certain metal ions, based on the color of the flame. The reaction is:It involves the burning of the sample, so (D) Flame test matches with II.

Thus, the correct matches are: A-III, B-IV, C-I, D-II.

Answer 2

Cobalt nitrate test}: MCO$_3 \rightarrow$ MO \quad Co(NO$_3$)$_2$ $\xrightarrow{\Delta}$ CoO, MO.
Flame test: MCO$_3 \rightarrow$ MCl$_2 \rightarrow$ M$^{2+}$.
Borax bead test: MSO$_4$ + Na$_2$B$_4$O$_7$ $\xrightarrow{\Delta}$ M(BO$_2$)$_2 \rightarrow$ MBO$_2 \rightarrow$ M$.
Charcoal cavity test: MSO$_4$ + Na$_2$CO$_3$ $\xrightarrow{\Delta}$ MCO$_3 \rightarrow$ MO $\rightarrow$ M.
The correct matching is: A-III, B-IV, C-I, D-II.
Final Answer: A-III, B-IV, C-I, D-II.