Which of the following is reddish brown

Options

A. NO
B. `NO_(2)`
C. `N_(2)O`
D. `NH_(3)`

Answer

To answer the question "Which of the following is reddish brown?" we will follow these steps:

### Step 1: Identify the options
First, we need to identify the options provided in the question. Since the options are not listed, we will assume they are oxides of nitrogen, as mentioned in the video transcript.

### Step 2: Understand the properties of nitrogen oxides
Nitrogen oxides include several compounds, but the most relevant ones for this question are:
- Nitric oxide (NO)
- Nitrogen dioxide (NO2)
- Dinitrogen tetroxide (N2O4)
- Nitrous oxide (N2O)

### Step 3: Determine the color of each oxide
- **Nitric oxide (NO)**: This gas is colorless.
- **Nitrogen dioxide (NO2)**: This gas is reddish-brown in color.
- **Dinitrogen tetroxide (N2O4)**: This gas is colorless at low temperatures but can appear as a reddish-brown gas when in equilibrium with NO2.
- **Nitrous oxide (N2O)**: This gas is colorless.

### Step 4: Identify the reddish-brown oxide
From the above analysis, we can conclude that the reddish-brown gas among the nitrogen oxides is **Nitrogen dioxide (NO2)**.

### Conclusion
Thus, the answer to the question "Which of the following is reddish brown?" is **NO2 (Nitrogen dioxide)**.

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