Match List-I with List-II
| List-I | List-II |
| Chemicals | Applications |
| (A) Methylene chloride | (I) Antiseptic |
| (B) Triiodomethane | (II) Paint remover |
| (C) Trichloromethane | (III) Fire extinguisher |
| (D) Tetrachloromethane | (IV) Freon refrigerant |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (A) - (II), (B) - (I), (C) - (IV), (D) - (III)
The polyhalogen compounds of methane have well-known uses, which follow from their properties (good solvents, antiseptic action, non-inflammability):
(A) Methylene chloride — This matches (II) Paint remover. Dichloromethane (\( \ce{CH2Cl2} \)) is a good solvent and is used as a paint remover, in metal cleaning and as a propellant in aerosols.
(B) Triiodomethane — This matches (I) Antiseptic. Iodoform (\( \ce{CHI3} \)) was used as an antiseptic; its action is due to the free iodine it releases, not to the compound itself. Its objectionable smell has led to its replacement by other iodine compounds.
(C) Trichloromethane — This matches (IV) Freon refrigerant. Chloroform (\( \ce{CHCl3} \)) is itself not a refrigerant, but it is mainly used for the production of the freon refrigerant R-22 (\( \ce{CHClF2} \)).
\( \displaystyle \ce{CHCl3 + 2HF -> CHClF2 + 2HCl} \)
(D) Tetrachloromethane — This matches (III) Fire extinguisher. Carbon tetrachloride (\( \ce{CCl4} \)) is dense and does not burn; its heavy vapour covers the fire and cuts off air, so it was used in fire extinguishers.
Shortcut: (D)–(III) appears only in Options (1) and (2), and (B)–(I) then leaves only Option (1).