| Industrial Smog |
|
There are two general types of smog namely industrial smog and photochemical smog. Industrial smog, produced largely from the combustion of coal and oil, is high in particulates. Its main chemical ingredient is sulfur dioxide, which accumulates in aerosols and is transformed to sulfuric acid:
|
 |
|
Breathing aerosols containing even very low concentrations of sulfuric acid can cause severe breathing distress. Airborne sulfuric acid is also a leading cause of acid rain. |
| Prime source of the Photochemical smog is internal-combustion engine. Photochemical smog is produced by the action of sunlight on nitrogen oxides, hydrocarbons, and other pollutants created from fossil fuel combustion. Photochemical smog consists of pollutants that participate either directly or indirectly in chemical reactions induced by sunlight. These pollutants are predominately nitrogen oxides, ozone, and hydrocarbons.
|
|
Motor vehicles produce exhaust gases containing oxides of nitrogen such as nitrogen dioxide (NO2) and nitrogen monoxide (NO). At the high temperatures of the car's combustion chamber (cylinder), nitrogen and oxygen from the air react to form nitric oxide (NO):
|
 |
|
Nitrogen monoxide is fairly reactive. Once released from the engine, it reacts rapidly with atmospheric oxygen to form nitrogen dioxide:
|
 |
|
Nitrogen dioxide is a powerful corrosive agent that acts on metal, stone, and even human tissue. Its brown color is responsible for the brown haze typically seen over a polluted city. Sunlight initiates the transformation of nitrogen dioxide to nitric acid, HNO3, which, along with sulfuric acid, is a prime component of acid rain. In aerosols, sunlight splits nitrogen dioxide into nitrogen monoxide and atomic oxygen: |
 |
|
The nitrogen monoxide reacts with atmospheric oxygen to re-form nitrogen dioxide, and the atomic oxygen reacts with atmospheric oxygen to form ozone: |
 |
| Previous | Next
|
