Leaching of an ore is done by

Options

A. Hall's process
B. Serpeck's process
C. Cyanide process
D. Hall-Heroult process

Answer

**Step-by-Step Solution:**

1. **Understanding Leaching:**
- Leaching is a process used to extract minerals from solid ores by dissolving them in a liquid. This can occur naturally or be facilitated through industrial methods.

2. **Identifying the Processes:**
- The question lists several processes: Hall's process, Serpex process, Cyanide process, and Hall-Herold process. We need to determine which of these is specifically related to the leaching of ores.

3. **Analyzing Each Process:**
- **Hall's Process:** This is primarily used for the electrolysis of aluminum oxide (Al2O3) to produce aluminum. It is not a leaching process.
- **Serpex Process:** This involves the hydrolysis of aluminum nitride to produce aluminum hydroxide. This is also not a leaching process.
- **Cyanide Process:** This process involves the use of sodium cyanide to extract gold from its ore. The cyanide ions form complex ions with gold, making it a leaching process.
- **Hall-Herold Process:** Similar to Hall's process, this involves electrolysis and is used for aluminum production. It does not pertain to leaching.

4. **Conclusion:**
- Among the options provided, the **Cyanide Process** is the one that specifically describes the leaching of an ore, particularly for gold extraction.

**Final Answer:**
Leaching of an ore is done by the **Cyanide process**.

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