How will test whether a given solid has been purified or not ?

Explanation

To determine whether a given solid has been purified or not, you can follow these steps:

### Step 1: Determine the Melting Point
- **Procedure**: Take a small sample of the solid and place it in a melting point apparatus or a suitable setup to measure the melting point. Gradually heat the sample and record the temperature at which it starts to melt and the temperature at which it completely melts.
- **Expected Result**: A pure substance has a sharp melting point, while an impure substance will have a lower and broader melting range.

### Step 2: Compare with Literature Values
- **Procedure**: Compare the melting point you obtained with the known melting point of the pure substance from literature. For example, naphthalene has a melting point of 80°C.
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