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(i) Give the possible reason for the rel...

(i) Give the possible reason for the relative reactivities when iodide ions in acetone solution reacts with MeBr, EtBr, iso-prBr and t-BuBr under condition where only the `S_(N)2` mechanism operates. The relative reactivities were found to be 10,000: 65:0.50:0,0:039.
(ii) In an `S_(N)2)` reaction there relative reactivities are not observed in `S_(N)1` condition.

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### Step-by-Step Solution: **(i) Relative Reactivities in SN2 Mechanism:** 1. **Understanding SN2 Mechanism:** - The SN2 (Substitution Nucleophilic Bimolecular) mechanism involves a single concerted step where the nucleophile attacks the substrate simultaneously as the leaving group departs. The rate of the reaction is influenced by steric hindrance around the carbon atom that is being attacked. 2. **Analyzing the Compounds:** ...
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