Which of the following has more acid strength than the other:
o-Nitrophenol and m-Nitrophenl

Explanation

To determine which compound has more acid strength between ortho-nitrophenol and meta-nitrophenol, we can follow these steps:

### Step 1: Understand the Structures
- **Ortho-nitrophenol** has a nitro group (-NO2) attached to the benzene ring at the ortho position relative to the hydroxyl group (-OH).
- **Meta-nitrophenol** has the nitro group attached at the meta position relative to the hydroxyl group.

### Step 2: Identify the Effects of the Nitro Group
- The nitro group is an electron-withdrawing group. Its presence affects the acidity of the hydroxyl group in phenols.
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