Question

How can photochemical smog be controlled?

• A. By using catalytic convertors in the automobiles/industry.
• B. By complete combustion of fuel.
• C. By using catalyst.
• D. By using tall chimneys.

Hint:

To control photochemical smog, reducing emissions of nitrogen oxides (NOx) and volatile organic compounds (VOCs) using catalytic converters is the most effec tive solution.

Answer 1

The Correct Option is A

Photochemical smog, often referred to as "summer smog," is a type of air pollution that results from the interaction between sunlight and pollutants like nitrogen oxides (NO_x) and volatile organic compounds (VOCs). These pollutants are primarily emitted by automobiles and industrial facilities. The following explains how photochemical smog can be controlled:

1. Use of Catalytic Converters:
   Catalytic converters are devices installed in the exhaust system of vehicles. They convert harmful pollutants like nitrogen oxides (NO_x), hydrocarbons, and carbon monoxide into less harmful emissions such as nitrogen gas (N₂), water (H₂O), and carbon dioxide (CO₂).
   This method significantly reduces the precursors of photochemical smog and is widely used in controlling emissions from automobiles and industries.
2. Complete Combustion of Fuel:
   Ensuring complete combustion helps in reducing the emission of pollutants. However, complete combustion primarily reduces emissions related to hydrocarbons and carbon monoxide rather than directly controlling photochemical smog formation.
3. Use of Catalysts:
   While catalysts are useful in various chemical processes, their application is more indirect in this context compared to the specific role of catalytic converters in reducing vehicular emissions.
4. Use of Tall Chimneys:
   Using tall chimneys can disperse pollutants higher into the atmosphere, diluting their concentration at ground level. However, it does not necessarily prevent the chemical reactions that lead to the formation of photochemical smog.

Based on the explanations above, the most effective method to control photochemical smog is by using catalytic convertors in the automobiles/industry.