`Mn_2O_7` is a basic oxide.

Explanation

To determine whether \( \text{Mn}_2\text{O}_7 \) is a basic oxide, we need to analyze the oxidation state of manganese in this compound and its implications for acidity and basicity.

### Step-by-Step Solution:

1. **Identify the Oxidation State of Manganese in \( \text{Mn}_2\text{O}_7 \)**:
- In \( \text{Mn}_2\text{O}_7 \), there are 2 manganese (Mn) atoms and 7 oxygen (O) atoms.
- The oxidation state of oxygen is typically -2.
- Therefore, the total oxidation contribution from oxygen is \( 7 \times (-2) = -14 \).
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