Step 1: Understanding the Question:
The question asks for the specific nitrogen oxide that contributes to the thinning of the ozone layer in the stratosphere.
The ozone layer protects Earth from harmful ultraviolet (\(UV\)) radiation.
Step 2: Detailed Explanation:
Role of Nitric Oxide (\(NO\)):
While chlorofluorocarbons (\(CFCs\)) are the main cause of ozone depletion, nitrogen oxides also play a significant role.
Nitric Oxide (\(NO\)) is released into the stratosphere from various sources, including the exhaust of supersonic jet planes and the breakdown of nitrous oxide (\(N_2O\)) from fertilizers by \(UV\) light.
Mechanism of Depletion:
\(NO\) acts as a catalyst in the destruction of ozone (\(O_3\)). The reactions are as follows:
1. \(NO + O_3 \rightarrow NO_2 + O_2\)
2. \(NO_2 + O \text{ (atomic oxygen)} \rightarrow NO + O_2\)
Net Reaction: \(O_3 + O \rightarrow 2O_2\)
Catalytic Nature:
In this cycle, the \(NO\) molecule is consumed in the first step but regenerated in the second. This means a single molecule of \(NO\) can destroy thousands of ozone molecules before it is eventually removed from the atmosphere.
Other Oxides:
- \(N_2O\) (Nitrous oxide) is stable in the lower atmosphere but acts as a source for \(NO\) in the stratosphere.
- \(NO_2\) is an intermediate in the cycle.
- \(N_2O_3\) is not a significant stratospheric pollutant involved in this process.
Step 3: Final Answer:
Nitric Oxide (\(NO\)) is the primary oxide of nitrogen responsible for the catalytic depletion of the ozone layer.