A sheet of pure copper is used as :

Options

A. cathode
B. anode
C. positrode
D. negatrode

Answer

To answer the question "A sheet of pure copper is used as:", we need to analyze the role of the copper sheet in the context of electroplating and the function of electrodes.

### Step-by-Step Solution:

1. **Understanding Electroplating**:
- Electroplating is a process that uses electric current to reduce dissolved metal cations so that they form a coherent metal coating on an electrode.

2. **Identifying the Electrodes**:
- In an electroplating setup, there are two electrodes: the anode and the cathode. The anode is the electrode where oxidation occurs, and the cathode is where reduction takes place.

3. **Role of the Pure Copper Sheet**:
- In this scenario, the pure copper sheet is connected to the negative terminal of the power supply, making it the cathode.

4. **Function of the Cathode**:
- As the cathode, the pure copper sheet attracts metal cations from the electrolyte solution. These cations are reduced and deposit onto the surface of the cathode, effectively plating it with metal.

5. **Conclusion**:
- Therefore, the sheet of pure copper is used as a cathode in the electroplating process, where it serves as the surface onto which metal is deposited.

### Final Answer:
A sheet of pure copper is used as a **cathode** in the electroplating process.

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