Troposphere |
- Region where we are living.
- Contains 90% of the mass of the atmosphere.
- Starts at ground level with 228 K and ends at 18 km (200 K) with 6 K drop in temperature per km altitude.
- Beyond 18 km, temperature rises. This inflection point is called “Tropopause”.
- Tropopause divides troposphere from stratosphere.
- Atmospheric boundary layer - 2 km from the ground level.
- Combustion byproducts instantly affects this region.
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Photochemical chain reaction begin with dissociation of ozone as given below
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--------(1) |
The atomic oxygen
 reacts with water vapor to form hydroxyl radical
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--------(2) |
The OH radical reacts with CO and initiates other chain reactions as below
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--------(3) |
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--------(4) |
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