Why do we not prefer to prepare original solution of cations in conc. `H_(2)SO_(4)` or conc. `HNO_(3)`?

Explanation

### Step-by-Step Solution:

1. **Understanding the Context**: The question asks why concentrated sulfuric acid (H₂SO₄) and concentrated nitric acid (HNO₃) are not preferred for preparing original solutions of cations for qualitative analysis.

2. **Role of Concentrated Acids**: Both concentrated H₂SO₄ and HNO₃ are strong acids and also act as oxidizing agents. This means they can react with other substances, potentially altering them.

3. **Oxidizing Nature of Acids**:
- Concentrated H₂SO₄ can oxidize certain compounds. For example, when H₂S (hydrogen sulfide), which is commonly used for detecting group 2 metals, is introduced, it can be oxidized by H₂SO₄.
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