Which one absorbs U.V. radiation in stratosphere?

Options

A. `CO_(2)`
B. `N_(2)`
C. `O_(3)`
D. `H_(2)`

Answer

To solve the question "Which one absorbs U.V. radiation in stratosphere?" we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The options provided are carbon dioxide, nitrogen, ozone, and H2 (hydrogen gas).

2. **Understand the Role of the Stratosphere**: The stratosphere is the second major layer of Earth's atmosphere, situated above the troposphere and below the mesosphere. It contains the ozone layer, which is crucial for absorbing ultraviolet (UV) radiation from the sun.

3. **Analyze Each Option**:
- **Carbon Dioxide (CO2)**: While CO2 is a greenhouse gas, it does not significantly absorb UV radiation.
- **Nitrogen (N2)**: Nitrogen is the most abundant gas in the atmosphere, but it does not absorb UV radiation.
- **Ozone (O3)**: Ozone is known for its ability to absorb UV radiation. It is primarily found in the upper stratosphere and plays a critical role in protecting life on Earth by absorbing harmful UV rays.
- **Hydrogen (H2)**: Hydrogen gas does not absorb UV radiation.

4. **Conclusion**: Based on the analysis, ozone (O3) is the only option that absorbs UV radiation in the stratosphere. It acts as a protective shield, preventing harmful UV rays from reaching the Earth's surface.

5. **Final Answer**: The correct answer is **ozone (O3)**.