Extraction of metal from the ore cassiterite involves

Options

A. Carbon reduction of an oxide ore
B. Self-reduction of sulphide ore
C. Removal of copper impurity
D. Removal of iron impurity

Explanation

To extract metal from the ore cassiterite (SnO2), the following steps are involved:

### Step-by-Step Solution:

1. **Identify the Ore**: Cassiterite is primarily composed of tin oxide (SnO2). This is the starting material for the extraction of tin.

2. **Reduction Process**: The extraction of tin from cassiterite involves a reduction process. The first step is to treat SnO2 with carbon. The carbon acts as a reducing agent.

- **Chemical Reaction**:
\[ \text{SnO}_2 + \text{C} \rightarrow \text{Sn} + \text{CO}_2 \]
- In this reaction, tin (Sn) is produced along with carbon dioxide (CO2).

3. **Handling Remaining SnO2**: If there is any remaining SnO2 after the first reduction, it is treated again with carbon to ensure complete reduction.

- **Second Reaction**:
\[ \text{SnO}_2 + \text{C} \rightarrow \text{Sn} + \text{CO} \]
- Here, carbon monoxide (CO) is produced as a byproduct.

4. **Impurity Removal**: During the extraction process, impurities such as iron (Fe) may be present in the form of iron oxide (FeO or Fe2O3). To remove these impurities, silica (SiO2) is added.

- **Formation of Slag**:
\[ \text{FeO} + \text{SiO}_2 \rightarrow \text{FeSiO}_3 \text{ (slag)} \]
- The slag (FeSiO3) can be removed, leaving behind purer tin.

5. **Final Product**: The final product obtained from the reduction of cassiterite is metallic tin (Sn), which can then be further purified if necessary.

### Conclusion:
The extraction of metal from cassiterite involves the reduction of tin oxide using carbon and the removal of iron impurities by forming slag with silica.