Which of the following is more volatile : o-nitrophenol or p-nitrophenol?

Explanation

To determine which compound is more volatile between o-nitrophenol and p-nitrophenol, we need to analyze their molecular structures and the type of hydrogen bonding they exhibit.

### Step-by-Step Solution:

1. **Identify the Structures**:
- **o-Nitrophenol** (ortho-nitrophenol) has the nitro group (-NO2) positioned adjacent to the hydroxyl group (-OH) on the benzene ring.
- **p-Nitrophenol** (para-nitrophenol) has the nitro group positioned opposite to the hydroxyl group on the benzene ring.

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