What is the role of `CO_(2)` in the extractive metallurgy of aluminium from its ore ?

Explanation

### Step-by-Step Solution:

1. **Introduction to the Process**: The extraction of aluminum from its ore typically involves the Bayer process, where bauxite ore is treated with sodium hydroxide (NaOH) to extract aluminum oxide (Al₂O₃).

2. **Role of CO₂**: In the next step, the solution containing aluminum oxides and silicon oxides is treated with carbon dioxide (CO₂) gas.

3. **Formation of Carbonic Acid**: The CO₂ reacts with water in the solution to form carbonic acid (H₂CO₃), which is a weak acid.

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