Name the following
A compound which is added to lower the fusion temperature of the electrolytic bath in the extraction of aluminium .

Explanation

To answer the question regarding the compound added to lower the fusion temperature of the electrolytic bath in the extraction of aluminum, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Main Compound**: The primary compound used in the extraction of aluminum is alumina, which is represented by the chemical formula Al₂O₃. However, alumina has a very high fusion temperature of about 2100°C.

2. **Need for Lowering Fusion Temperature**: Since the high fusion temperature of alumina requires a significant amount of energy for extraction, it is necessary to lower this temperature to make the extraction process more efficient and cost-effective.

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