Describe the action of alcoholic potassium hydroxide (alc. KOH) on n-propyl bromide.

Explanation

### Step-by-Step Solution:

1. **Identify the Reactants**:
We have n-propyl bromide (C3H7Br) and alcoholic potassium hydroxide (alc. KOH).

2. **Understanding the Reaction Type**:
The reaction between n-propyl bromide and alcoholic KOH is an elimination reaction, specifically an E2 mechanism. In this mechanism, a base abstracts a proton (H) from the β-carbon while simultaneously the leaving group (Br) departs from the α-carbon.

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