`MnO_(2)` used as a catalyst in the preparation of oxygen from `KClO_(3)` should be completely free of carbon. Justify.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Role of MnO₂**:
- MnO₂ (manganese dioxide) is used as a catalyst in the decomposition of potassium chlorate (KClO₃) to produce oxygen gas. A catalyst is a substance that speeds up a chemical reaction without being consumed in the process.

2. **Impurities in MnO₂**:
- If MnO₂ contains carbon impurities, these can interfere with the catalytic process. Carbon can react with potassium chlorate during the decomposition reaction.

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