The positive plates in voltage cells of -

Options

A. Copper
B. Silicon
C. Zinc
D. Carbon

Explanation

### Step-by-Step Solution:

1. **Understanding the Components of a Voltage Cell**:
- A voltage cell consists of two electrodes: an anode and a cathode. The anode is where oxidation occurs, and the cathode is where reduction takes place.

2. **Identifying the Electrodes**:
- In a typical voltage cell, one of the electrodes is made of copper (Cu) and the other is made of zinc (Zn). The copper rod is usually the positive electrode (cathode), while the zinc rod is the negative electrode (anode).

3. **Determining the Positive Plate**:
- The question asks for the positive plate in the voltage cell. Since the copper rod acts as the cathode, it is the positive plate of the voltage cell.

4. **Conclusion**:
- Therefore, the positive plate in a voltage cell is **Copper**.

### Final Answer:
The positive plate in a voltage cell is **Copper**.

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