Leaching can be used for extraction of

Options

A. `Pb`
B. `Al`
C. `Ag`
D. `Au`

Answer

To solve the question regarding which metals can be extracted using leaching, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Leaching**:
- Leaching is a process used to extract metals from their ores by dissolving them in a suitable solvent. This solvent can be an acid, base, or other chemical reagents. The key aspect of leaching is that the desired metal ore must be soluble in the chosen solvent, while the gangue (unwanted materials) remains insoluble.

2. **Identifying the Metals in the Options**:
- The metals provided in the options are:
- PB (Lead)
- AL (Aluminum)
- AG (Silver)
- AU (Gold)

3. **Analyzing Each Metal**:
- **Lead (PB)**: Lead ores are typically not extracted using leaching methods; they are usually processed through smelting.
- **Aluminum (AL)**: Aluminum ores, such as bauxite, can be extracted using leaching methods, particularly with sodium hydroxide.
- **Silver (AG)**: Silver can be extracted using leaching methods, often using cyanide solutions.
- **Gold (AU)**: Gold is also extracted using leaching methods, commonly through cyanidation.

4. **Conclusion**:
- Based on the analysis, leaching can be used for the extraction of Aluminum (AL), Silver (AG), and Gold (AU). Therefore, the correct options are AL, AG, and AU.

### Final Answer:
Leaching can be used for the extraction of Aluminum (AL), Silver (AG), and Gold (AU).