Manganese dioxide is used in

Options

A. Pigment industry
B. dry battery cells
C. making coins
D. Photography

Answer

**Step-by-Step Solution:**

1. **Identify Manganese Dioxide**: Manganese dioxide is a chemical compound with the formula MnO₂. It is an important compound of manganese, a transition metal.

2. **Determine its Applications**: Manganese dioxide has various applications, but we need to focus on its specific use in batteries.

3. **Leclanché Cell**: Manganese dioxide is used in the Leclanché cell, which is a type of dry cell battery. This battery is commonly used in applications such as flashlights and remote controls.

4. **Role of Manganese Dioxide**: In the Leclanché cell, manganese dioxide acts as a depolarizer. A depolarizer is a substance that helps to prevent the buildup of gases at the electrodes, which can hinder the flow of current.

5. **Moisture Production**: Additionally, manganese dioxide helps to maintain moisture within the cell. This moisture is crucial for the ionic mobility of the electrolyte, which enhances the efficiency of the battery.

6. **Conclusion**: Therefore, manganese dioxide is primarily used in dry batteries, specifically in the Leclanché cell, where it serves as a depolarizer and helps maintain moisture for better ionic mobility.

**Final Answer**: Manganese dioxide is used in Leclanché cells (dry batteries).

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