Silver from argentiferous lead is obtained by

Options

A. Parkes process
B. Serpeck process
C. Down's process
D. Castner-Kellner process

Answer

To solve the question "Silver from argentiferous lead is obtained by," we will analyze the options provided and determine the correct process step by step.

### Step-by-Step Solution:

1. **Understanding Argentiferous Lead**: Argentiferous lead is lead that contains silver. The silver is typically present in the form of silver sulfide (Ag2S) or other silver compounds.

2. **Identifying the Processes**: We have four options to consider:
- A) Parkes process
- B) Serpex process
- C) Downs process
- D) Kastner-Kellner process

3. **Analyzing Each Process**:
- **Parkes Process**: This process is specifically designed for extracting silver from argentiferous lead. It involves the use of sodium cyanide (NaCN) to form a complex with silver, which can then be precipitated out using zinc.
- **Serpex Process**: This process is related to the purification of aluminum from bauxite, not silver.
- **Downs Process**: This process is used to obtain sodium from molten sodium fluoride, and it does not involve silver extraction.
- **Kastner-Kellner Process**: This process involves the production of alkali hydroxides and is not related to silver extraction.

4. **Conclusion**: The only process that specifically deals with the extraction of silver from argentiferous lead is the Parkes process.

### Final Answer:
Silver from argentiferous lead is obtained by the **Parkes process**.