Which of the following is reddish brown pollutant gas?

Options

A. `MO`
B. `N_(2)O`
C. `NO_(2)`
D. `NH_(3)`

Answer

To determine which of the following is a reddish-brown pollutant gas, we can analyze the given options step by step:

1. **Understanding Pollutants**: A pollutant is a substance that undesirably affects the environment. We need to identify which of the provided options is a reddish-brown gas.

2. **Analyzing the Options**:
- **Option 1: MO (Molybdenum)**: This is a dark grey color pollutant that affects agricultural land. Since it is dark grey, it cannot be the reddish-brown gas we are looking for.
- **Option 2: N2O (Dinitrogen Oxide)**: This gas is colorless and is known to damage the ozone layer. Therefore, it is not the reddish-brown gas.
- **Option 3: NO2 (Nitrogen Dioxide)**: This gas is known to create a reddish-brown haze in the environment. It also reacts with water vapor to produce nitric acid rain, which is harmful. This fits the description of a reddish-brown pollutant gas.
- **Option 4: NH3 (Ammonia)**: Ammonia is a colorless gas that can cause respiratory issues and eye irritation. Since it is colorless, it does not qualify as the reddish-brown gas.

3. **Conclusion**: Based on the analysis, the reddish-brown pollutant gas is **Option 3: NO2 (Nitrogen Dioxide)**.

**Final Answer**: The reddish-brown pollutant gas is Nitrogen Dioxide (NO2).

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