Concept:The Iodoform reaction is a highly specific cleavage reaction that occurs exclusively when a methyl group is adjacent to a carbonyl carbon (\( CH_3-CO- \)).
Solution:- The reagents \( Na_2CO_3 \) (a mild base) and Iodine (\( I_2 \)) create the haloform conditions.
- Acetone (Propanone) has the structure \( CH_3-CO-CH_3 \).
- Because it contains the required terminal methyl ketone group, it rapidly undergoes triple iodination followed by base cleavage to yield the yellow precipitate of iodoform (\( CHI_3 \)).
Why other options are incorrect:Methanol lacks the \( CH_3-CH(OH)- \) structure. Acetic acid and acetic anhydride contain the \( CH_3-CO- \) group but are shielded by their resonance and leaving group dynamics (carboxylic acid derivatives do not undergo the haloform reaction).
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