Distinction between pairs of compounds
1, 1-Dichloroethane and 1, 2-dichloroethane.

Explanation

To distinguish between 1,1-dichloroethane and 1,2-dichloroethane, we can observe their reactions with zinc. Here’s a step-by-step solution:

### Step 1: Understand the Structures
- **1,1-Dichloroethane** has the structure:
CH2Cl-CH2Cl
- **1,2-Dichloroethane** has the structure:
CH2Cl-CHCl

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