Which one of the following is NOT a component of photochemical smog ?
Ozone
Peroxyacetyl nitrate
Polyaromatic hydrocarbons
Nitric oxide
Answer is Right!
Answer is Wrong!
This question was previously asked in
UPSC CAPF – 2020
Photochemical smog is primarily formed by the reaction of nitrogen oxides (NOx, primarily NO and NO2) and volatile organic compounds (VOCs) in the presence of sunlight. Key components produced by these reactions include ozone (O3), peroxyacetyl nitrates (PANs), aldehydes, ketones, and nitric acid. Nitric oxide (NO) is a precursor pollutant, quickly converted to NO2 which drives the photochemical process, so it is also present in the mixture. Polyaromatic hydrocarbons (PAHs) are complex organic compounds produced mainly from the incomplete combustion of organic matter (like in vehicle exhaust or burning wood). While PAHs are often present in polluted urban air (which experiences smog) and contribute to particulate matter, they are not formed *by* the photochemical reactions themselves.