The gas emitted by supersonic jet planes that slowly depletes the ozone layer is

Options

A. CO
B. NO
C. `SO_2`
D. `O_2`

Answer

To answer the question regarding the gas emitted by supersonic jet planes that slowly depletes the ozone layer, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Emission Source**: Supersonic jet planes emit various gases during their operation, particularly at high altitudes where they fly.

2. **Recognize the Key Gas**: Among the gases emitted, one significant gas is nitric oxide (NO). This is the gas that is primarily responsible for the depletion of the ozone layer.

3. **Understand the Reaction Mechanism**:
- When nitric oxide (NO) is released into the atmosphere, it can react with ozone (O₃).
- The reaction can be represented as:
\[ \text{NO} + \text{O}_3 \rightarrow \text{NO}_2 + \text{O}_2 \]
- In this reaction, nitric oxide reacts with ozone to form nitrogen dioxide (NO₂) and molecular oxygen (O₂).

4. **Further Reactions**:
- The nitrogen dioxide (NO₂) can further react with ultraviolet (UV) light, which leads to the formation of nascent oxygen (O).
- This nascent oxygen can then react with more ozone:
\[ \text{NO}_2 + \text{O} \rightarrow \text{NO} + \text{O}_2 \]
- This cycle continues, leading to a net depletion of ozone in the stratosphere.

5. **Conclusion**: The gas emitted by supersonic jet planes that contributes to the slow depletion of the ozone layer is nitric oxide (NO).

### Final Answer:
The gas emitted by supersonic jet planes that slowly depletes the ozone layer is **Nitric Oxide (NO)**.

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