Match List - I with List - II.

(a)	(i) Hell-Volhard-Zelinsky reaction
(b)	(ii) Gattermann-Koch reaction
(c)	(iii) Haloform reaction
(d)	(iv) Esterification

Choose the correct answer from the options given below.

The correct answer is: (a)-(ii), (b)-(iii), (c)-(iv), (d)-(i)

Let us analyze each reaction shown in the images and match it with the correct named reaction from List-II.

Reaction (a): The image shows benzene reacting with CO, HCl in the presence of Anhydrous AlCl₃/CuCl.

This is a classic formylation reaction where carbon monoxide and HCl act as the formylating agent, with anhydrous AlCl₃ (a Lewis acid catalyst) and CuCl as co-catalyst, to introduce an aldehyde group (−CHO) onto the benzene ring, producing benzaldehyde.

This is the Gattermann-Koch reaction — a method for preparing aromatic aldehydes by treating an aromatic compound with CO and HCl in the presence of AlCl₃ and CuCl.

∴ (a) → (ii) Gattermann-Koch reaction

Reaction (b): The image shows a compound with the structure R−CO−CH₃ (a methyl ketone) reacting with NaOX (sodium hypohalite, where X = Cl, Br, or I).

When a methyl ketone (R−COCH₃) is treated with a sodium hypohalite (NaOX), the methyl group adjacent to the carbonyl is trihalogenated, and the resulting trihalomethyl group (CX₃) is cleaved off as a haloform (CHX₃), leaving behind a carboxylate salt (RCOONa).

This is the Haloform reaction — a well-known reaction specific to methyl ketones and secondary alcohols of the type CH₃−CH(OH)−R.

∴ (b) → (iii) Haloform reaction

Reaction (c): The image shows R−CH₂−OH (a primary alcohol) reacting with R'COOH (a carboxylic acid) in the presence of Conc. H₂SO₄.

When an alcohol reacts with a carboxylic acid in the presence of concentrated sulphuric acid (which acts as a dehydrating agent and catalyst), an ester is formed along with water. This is a condensation reaction:

R−CH₂−OH + R'COOH $\stackrel{H_2{\mathrm{SO}}_4}{\to }$ R'COOCH₂R + H₂O

This is the Esterification reaction — specifically Fischer esterification, where an acid and an alcohol combine to form an ester.

∴ (c) → (iv) Esterification

Reaction (d): The image shows R−CH₂−COOH (a carboxylic acid with an α-hydrogen) reacting with (i) X₂/Red P (halogen with red phosphorus) followed by (ii) H₂O (hydrolysis).

When a carboxylic acid having an α-hydrogen is treated with a halogen (Cl₂ or Br₂) in the presence of red phosphorus (which generates the phosphorus trihalide PX₃ in situ), halogenation occurs specifically at the α-carbon. The red phosphorus first converts the acid to an acyl halide, which then undergoes α-halogenation. Subsequent hydrolysis gives the α-halo carboxylic acid.

R−CH₂−COOH → R−CHX−COOH

This is the Hell-Volhard-Zelinsky (HVZ) reaction — a reaction used for α-halogenation of carboxylic acids using Cl₂ or Br₂ in the presence of red phosphorus (or PBr₃).

∴ (d) → (i) Hell-Volhard-Zelinsky reaction

Final Matching:
(a) ��� (ii) Gattermann-Koch reaction
(b) → (iii) Haloform reaction
(c) → (iv) Esterification
(d) → (i) Hell-Volhard-Zelinsky reaction

This corresponds to option: (a)-(ii), (b)-(iii), (c)-(iv), (d)-(i).