NEET BIOLOGY

Detailed explanation-1: -Smog is formed when fog is mixed with smoke. The presence of unburnt hydrocarbons in air when mixed with condensed water vapour forms a thick layer called smog. It lowers the visibility during winters and is an indication of air pollution.

Detailed explanation-2: -Photochemical smog, which is also known as “Los Angeles smog, ” occurs most prominently in urban areas that have large numbers of automobiles. It requires neither smoke nor fog.

Detailed explanation-3: -Smog is air pollution that reduces visibility. The term “smog” was first used in the early 1900s to describe a mix of smoke and fog. The smoke usually came from burning coal. Smog was common in industrial areas, and remains a familiar sight in some cities today.

Detailed explanation-4: -Smog is made up of many chemicals including nitrogen oxides (NOx), sulphur dioxide (SOx), carbon monoxide (CO), and volatile organic compounds (VOCs), but the two main components of smog are particulate matter (PM) and ground-level ozone (O3).

Detailed explanation-5: -What is photochemical smog? Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities. It tends to occur more often in summer, because that is when we have the most sunlight.