FINKELSTEIN REACTION uses NaI (sodium iodide) in dry ACETONE to convert alkyl chlorides into alkyl iodides. The driving force is

1. NCERT §6.4 (Preparation of haloalkanes — Finkelstein reaction): 2. Equation: $\mathrm{R{-}Cl} + \mathrm{NaI} \xrightarrow{\text{dry acetone}} \mathrm{R{-}I} + \mathrm{NaCl}\downarrow$. 3. NaI is SOLUBLE in acetone; NaCl is INSOLUBLE — so NaCl precipitates out of the reaction mixture. 4. By Le Chatelier's principle, removing NaCl shifts the equilibrium to the right, driving the substitution to completion. 5. Without this trick, the equilibrium would lie far to the LEFT (C-Cl bond is stronger than C-I — alkyl chloride is thermodynamically preferred). The precipitation provides the thermodynamic push. 6. Option B is FALSE (C-Cl is stronger than C-I, not weaker). Option C ignores the actual driving force. Option D is not part of Finkelstein. _Source: NCERT Class 12 Chemistry Part 2, Ch 6, §6.4 (Preparation — Finkelstein reaction), p. 6._