Which of these are the applications of electrolysis?

Options

A. Metal Extraction
B. Electroplating
C. Electrorefining
D. All of these

Answer

To answer the question "Which of these are the applications of electrolysis?" we will analyze the options provided: metal extraction, electroplating, electrorefining, or all.

### Step-by-Step Solution:

1. **Understanding Electrolysis**:
- Electrolysis is a chemical process that uses electrical energy to drive a non-spontaneous reaction. It involves the breakdown of compounds into their individual elements or ions using an electric current.

2. **Identifying Applications**:
- **Metal Extraction**: Electrolysis is used in the extraction of metals from their ores. For example, aluminum is extracted from bauxite ore using electrolysis.
- **Electroplating**: This is a process where a layer of metal is deposited on a surface using electrolysis. It is commonly used to coat objects with a thin layer of metal for protection or aesthetic purposes.
- **Electrorefining**: This process is used to purify metals. For instance, copper can be purified using electrolysis, where impure copper acts as the anode and pure copper is deposited at the cathode.

3. **Conclusion**:
- Since all three processes (metal extraction, electroplating, and electrorefining) utilize electrolysis, the correct answer is "all".

### Final Answer:
- The applications of electrolysis include metal extraction, electroplating, electrorefining, and therefore the answer is **all**.