Sulphide ore of metal are usually concentrated by froth flotation process .Which one of the following sulphide3 ores after an exception and is contrated by electrical leaching?

Options

A. Galena
B. Copper pyrite
C. Sphalerite
D. Argenitite

Explanation

To solve the question regarding which sulphide ore is concentrated by electrical leaching instead of the froth flotation process, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Sulphide Ores**:
- The question mentions sulphide ores. Common examples include galena (PbS), copper pyrite (CuFeS₂), and argentite (Ag₂S).

2. **Understand the Froth Flotation Process**:
- Froth flotation is a method used to separate hydrophobic materials from hydrophilic ones. It is commonly used for the concentration of sulphide ores.

3. **Identify the Exception**:
- The question asks for an exception among the listed sulphide ores that is concentrated by electrical leaching.

4. **Analyze Each Ore**:
- **Galena (PbS)**: Typically concentrated by froth flotation.
- **Copper Pyrite (CuFeS₂)**: Also concentrated by froth flotation.
- **Argentite (Ag₂S)**: This ore is less reactive and is not effectively concentrated by froth flotation. Instead, it is concentrated using electrical leaching.

5. **Explain the Process for Argentite**:
- Argentite (Ag₂S) is treated with cyanide to form a complex, and then zinc is used to displace silver from this complex, allowing for the extraction of silver.

6. **Conclusion**:
- Based on the analysis, the sulphide ore that is an exception and is concentrated by electrical leaching is **argentite (Ag₂S)**.

### Final Answer:
The sulphide ore that is concentrated by electrical leaching instead of the froth flotation process is **argentite (Ag₂S)**.

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