Correct the following statements by changing the underlined part of the sentence :
Aluminium is obtained by `ul("carbon reduction")` of alumina.

Explanation

To correct the statement "Aluminium is obtained by carbon reduction of alumina," we need to replace the underlined part "carbon reduction" with the correct process used for extracting aluminium from alumina.

### Step-by-Step Solution:

1. **Identify the Process**: The extraction of aluminium from alumina (Al₂O₃) is not done by carbon reduction. Instead, it is primarily done through electrolysis.

2. **Correct the Underlined Part**: Replace "carbon reduction" with "electrolysis". The corrected statement will be:
- "Aluminium is obtained by **electrolysis** of alumina."
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