Following compounds are given to you :
2-Bromopentane, 2-Bromo-2-methylbutane, 1-Bromopentane
(i) Write the compound which is most reactive towards `S_(N) 2` reaction
(ii) Write the compound which is optically active
(iii) Write the compound which is most reactive towards `beta`-elimination reaction

Explanation

To solve the question, we need to analyze the three given compounds: 2-Bromopentane, 2-Bromo-2-methylbutane, and 1-Bromopentane. We will address each part of the question step by step.

### Step 1: Identify the Compounds
1. **2-Bromopentane**: This compound has a bromine atom attached to the second carbon of a pentane chain.
2. **2-Bromo-2-methylbutane**: This compound has a bromine atom attached to the second carbon of a butane chain, which also has a methyl group on the same carbon.
3. **1-Bromopentane**: This compound has a bromine atom attached to the first carbon of a pentane chain.

### Step 2: Determine Reactivity Towards SN2 Reaction
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