When pyrolusite is fused with KOH, the colour of the product is

Options

A. red
B. pink
C. black
D. green

Explanation

To determine the color of the product formed when pyrolusite (MnO2) is fused with KOH, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Pyrolusite**:
- Pyrolusite is the mineral form of manganese dioxide, which is represented by the chemical formula MnO2.

2. **Understand the Reaction**:
- When pyrolusite (MnO2) is fused with potassium hydroxide (KOH), a chemical reaction occurs. The reaction can be represented as:
\[ 2 \text{MnO}_2 + 4 \text{KOH} \rightarrow 2 \text{K}_2\text{MnO}_4 + 2 \text{H}_2\text{O} + \text{O} \]
- In this reaction, manganese dioxide reacts with potassium hydroxide to form potassium manganate (K2MnO4), water, and nascent oxygen.

3. **Identify the Product**:
- The main product of this reaction is potassium manganate (K2MnO4).

4. **Determine the Color of the Product**:
- Potassium manganate (K2MnO4) is known to have a green color.

5. **Conclusion**:
- Therefore, the color of the product formed when pyrolusite is fused with KOH is green.

### Final Answer:
The color of the product is **green**.

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