Which of the following is coloured ?

Options

A. `NO`
B. `N_2 O`
C. `NO_2`
D. `NH_3`

Answer

To determine which of the following compounds is colored, we will analyze each option provided:

1. **NO (Nitric Oxide)**:
- NO is a colorless gas. It is paramagnetic due to the presence of an unpaired electron, but it does not exhibit any color.

2. **N2O (Nitrous Oxide)**:
- N2O is also a colorless gas. It has a stable electronic configuration and does not have unpaired electrons that would contribute to color.

3. **NO2 (Nitrogen Dioxide)**:
- NO2 is a colored compound. It appears brown due to the presence of unpaired electrons and its molecular structure, which allows it to absorb certain wavelengths of light.

4. **NH3 (Ammonia)**:
- NH3 is a colorless gas. It has a stable electronic configuration with all electrons paired, contributing to its lack of color.

After analyzing all the options, we conclude that the colored compound among the given options is **NO2**.

**Final Answer**: The colored compound is **NO2**.

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