Zinc is extracted from zinc blende by

Options

A. Carbon reduction process
B. Nitrogen reduction process
C. Oxygen reduction process
D. All of these

Answer

To extract zinc from zinc blende (zinc sulfide), the following steps are involved:

### Step-by-Step Solution:

1. **Roasting of Zinc Blende**:
- Zinc blende (ZnS) is first subjected to roasting. This process involves heating the ore in the presence of excess air (oxygen) at a high temperature (around 1200 K).
- During roasting, zinc sulfide is converted into zinc oxide (ZnO) and sulfur dioxide (SO₂) is released as a byproduct.
- The reaction can be represented as:
\[ 2 \text{ZnS} + 3 \text{O}_2 \rightarrow 2 \text{ZnO} + 2 \text{SO}_2 \]

2. **Reduction of Zinc Oxide**:
- The zinc oxide obtained from the roasting process is then reduced to obtain zinc metal. This reduction is typically done using carbon (coke) at a high temperature (around 1673 K).
- The reaction for this reduction can be represented as:
\[ \text{ZnO} + \text{C} \rightarrow \text{Zn} + \text{CO} \]
- This step produces volatile zinc and carbon monoxide as a byproduct.

3. **Distillation of Zinc**:
- The volatile zinc produced during the reduction is collected by distillation. Since zinc has a low boiling point, it can be easily separated from the other materials.

4. **Electrolytic Refining**:
- To obtain pure zinc, the distilled zinc may undergo electrolytic refining. This process helps in removing impurities and produces high-purity zinc metal.

### Final Answer:
Zinc is extracted from zinc blende by roasting to form zinc oxide, followed by reduction of zinc oxide using carbon, and finally distillation and electrolytic refining to obtain pure zinc metal.

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