The process used in converting hydrated Alumina into anhydrous alumina is called

Options

A. Roasting
B. Calcination
C. Smelting
D. Dressing

Answer

To solve the question regarding the process used in converting hydrated alumina into anhydrous alumina, we can follow these steps:

### Step 1: Understand the Terms
- **Hydrated Alumina**: This is aluminum oxide (Al₂O₃) that contains water molecules in its structure.
- **Anhydrous Alumina**: This is aluminum oxide (Al₂O₃) that does not contain water.

### Step 2: Identify the Process
- The conversion of hydrated alumina to anhydrous alumina involves the removal of water from the hydrated form.

### Step 3: Know the Relevant Processes
- **Calcination**: This is a thermal treatment process where a material is heated to high temperatures in the absence of air or in a controlled atmosphere. This process is commonly used to remove water and other volatile substances from a compound.
- **Roasting**: This process involves heating sulfide ores in the presence of oxygen to convert them into oxides. It is not applicable here.
- **Smelting**: This process is used to extract metals from their ores by heating and melting. It is not relevant for the conversion of hydrated alumina.
- **Dressing**: This refers to the process of removing impurities from ores, which is not the focus of this question.

### Step 4: Conclusion
- The correct process for converting hydrated alumina into anhydrous alumina is **calcination**.

### Final Answer
The process used in converting hydrated alumina into anhydrous alumina is called **calcination**.

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