Extraction of aluminium form alumina is done by _____.

Answer

**Step-by-Step Solution:**

1. **Identify the Compound**: The first step is to recognize what alumina is. Alumina is chemically represented as Al₂O₃, which is the oxide of aluminum.

2. **Understand the Extraction Process**: To extract aluminum from alumina, we need to employ a method that can effectively separate aluminum from its oxide form.

3. **Know the Challenges**: One of the challenges in extracting aluminum from alumina is its high melting point of approximately 2000 degrees Celsius, which makes direct extraction difficult.

4. **Use of Flux**: To lower the melting point of alumina, we can add certain compounds. Calcium fluoride (CaF₂) and sodium aluminum fluoride (Na₃AlF₆) are commonly used as fluxes in this process. These compounds help to reduce the melting point of alumina, making it easier to work with.

5. **Electrolytic Process**: The extraction of aluminum is performed through an electrolytic process. In this setup, alumina is dissolved in a molten mixture of CaF₂ and Na₃AlF₆.

6. **Setup of Electrolysis**: In the electrolytic cell, there are two electrodes: an anode and a cathode. The alumina is introduced into the cell, and when electricity is passed through the solution, aluminum ions migrate to the cathode where they are reduced to form pure aluminum.

7. **Final Answer**: The process used for the extraction of aluminum from alumina is called **Electrometallurgy**.

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