How would you prepare tetraboric acid from boric acid?

Explanation

To prepare tetraboric acid (H2B4O7) from boric acid (H3BO3), you can follow these steps:

### Step-by-Step Solution:

1. **Preparation of Boric Acid from Borax**:
- Start with borax (Na2B4O7·10H2O), which is a natural mineral.
- Dissolve borax in a mineral acid (like hydrochloric acid, HCl). The reaction can be represented as:
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