Which of the following gases have brown colour ?

Options

A. `Br_(2)`
B. `NO_(2)`
C. `CO_(2)`
D. `I_(2)`

Answer

To determine which gases have a brown color, we can analyze the given options based on their properties.

### Step-by-Step Solution:

1. **Identify the Gases**:
- We need to identify the gases from the options provided. The question mentions gases, so we will focus on those that are in gaseous form.

2. **Examine Each Option**:
- **Iodine (I2)**: Iodine is primarily a solid at room temperature and appears violet in color. Therefore, it does not qualify as a gas with brown color.
- **Carbon Dioxide (CO2)**: Carbon dioxide is a colorless gas. It does not have any color, so it cannot be considered a brown gas.
- **Bromine (Br2)**: Bromine is a reddish-brown liquid at room temperature and can produce brown vapors when it evaporates. Thus, bromine is a gas that exhibits brown color.
- **Nitrous Oxide (N2O)**: Nitrous oxide is a colorless gas and does not have any brown color.

3. **Conclusion**:
- From the analysis, the gases that exhibit a brown color are **Bromine (Br2)** and the **Nitrogen Dioxide (NO2)**, which is often associated with reddish-brown color in its gaseous form.

### Final Answer:
The gases that have a brown color are **Bromine (Br2)** and **Nitrogen Dioxide (NO2)**.

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