An alkyl halide with molecular formula `C_(4)H_(5)Br` is optically active. What is its structure ?

Explanation

To determine the structure of the alkyl halide with the molecular formula C₄H₅Br that is optically active, we can follow these steps:

### Step 1: Analyze the Molecular Formula
The molecular formula C₄H₅Br indicates that we have a compound containing 4 carbon atoms, 5 hydrogen atoms, and 1 bromine atom.

### Step 2: Determine the Degree of Unsaturation
To find out how many double bonds or rings are present in the structure, we can calculate the degree of unsaturation (DU). The formula for calculating DU is:
\[ \text{DU} = \frac{(2C + 2 + N - H - X)}{2} \]
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