Q.Match the following:

Iodoform matches antiseptic (iii), carbon tetrachloride matches fire extinguisher (i), CFC matches refrigerant (iv), and DDT matches insecticide (ii) — giving option (a).

Each of these halogenated compounds has a well-known everyday use based on its chemical properties:

(1) Iodoform (CHI3) has mild antiseptic properties, largely due to the free iodine it slowly liberates, so it was traditionally used to dress wounds — matches (iii) Antiseptic.

(2) Carbon tetrachloride (CCl4) is non-flammable and, being denser than air, can blanket a fire and cut off its oxygen supply, so it was historically used in fire extinguishers (though now largely phased out for ozone and toxicity reasons) — matches (i) Fire extinguisher.

(3) Chlorofluorocarbons (CFCs) are chemically inert, non-toxic, and easily liquefied/vapourised, which made them ideal working fluids in refrigeration and air-conditioning systems — matches (iv) Refrigerants. …

Chloropicrin → soil sterilizer; methyl isocyanide → detection of primary amines; chlorobenzene → DDT manufacture; methylene chloride → paint remover.

Matching each compound to its standard use:

• (1) Chloro picrin (trichloronitromethane, CCl3NO2): used as a fumigant/soil sterilizer and insecticide → (iv).
• (2) Methyl isocyanide (CH3NC): the carbylamine (isocyanide) reaction — a primary amine + CHCl3 + alcoholic KOH gives a foul-smelling alkyl isocyanide — is the classic qualitative test used to detect primary amines → (i). …