Match List-I with List-II
|
List-I Compound |
List-II Use |
|
(A) Dichloromethane |
(I) in the manufacturing of propellants for aerosol cans |
|
(B) DDT |
(II) in the production of the Freon refrigerant R-22 |
|
(C) Trichloromethane |
(III) as a paint remover |
|
(D) Tetrachloromethane |
(IV) as an insecticide |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → (A)-(III), (B)-(IV), (C)-(II), (D)-(I)
Polyhalogen compounds have many industrial uses, mostly as solvents, as raw materials for refrigerants and propellants, and as insecticides.
(A) Dichloromethane — This matches (III) as a paint remover. \( \ce{CH2Cl2} \) is a widely used solvent; it strips paint and is also used in metal cleaning and as a process solvent.
(B) DDT — This matches (IV) as an insecticide. DDT (p,p′-dichlorodiphenyltrichloroethane) was the first chlorinated organic insecticide, used against the mosquitoes that spread malaria; it is now banned in many countries because it is not broken down and builds up in food chains.
(C) Trichloromethane — This matches (II) in the production of the Freon refrigerant R-22. Chloroform is fluorinated to chlorodifluoromethane, which is R-22:
\( \displaystyle \ce{CHCl3 + 2HF} \xrightarrow{\ce{SbCl5}} \ce{CHClF2 + 2HCl} \)
(D) Tetrachloromethane — This matches (I) in the manufacturing of propellants for aerosol cans. \( \ce{CCl4} \) is used to make chlorofluorocarbons, which served as refrigerants and as aerosol propellants.
Shortcut: DDT is an insecticide, and (B)-(IV) appears only in Option (4).
Note: The NCERT book gives dichloromethane two of these uses: it is used both as a paint remover (III) and as a propellant in aerosols (I), as given in the extract below. Only Option (4) gives a complete one-to-one match, so it is the answer.
NCERT (2026-27 edition):
Dichloromethane (Methylene Chloride) – “Dichloromethane is widely used as a solvent as a paint remover, as a propellant in aerosols, and as a process solvent in the manufacture of drugs.”
Trichloromethane (Chloroform) – “… The major use of chloroform today is in the production of the freon refrigerant R-22.”
Tetrachloromethane (Carbon Tetrachloride) – “It is produced in large quantities for use in the manufacture of refrigerants and propellants for aerosol cans.”