Question

Photochemical smog can impact visibility and human health in large metropolitan areas. Primary air pollutants are converted to secondary air pollutants to form smog in these areas. Which of these is most closely associated with being a secondary air pollutant?

A) ozone
B) nitrogen oxide
C) particulate matter
D) volatile organic compounds

Answer 1

Ozone.

Step-by-step explanation:

• Photo-chemical smog is an example of of secondary pollutant formed in congested metropolitan cities.
• It is mainly composed of compound like ozone, peroxy-acyl nitrates and nitric acid.
• It is formed under warm condition and is called brown air.
• Photo-chemical smog is mainly formed by primary pollutants like, hydrocarbons and nitrous oxide.
• Photo-chemical smog forms in the presence of sunlight.
• Photo-chemical smog adversely effects both plants and animals.

Answer 2

A) ozone

Step-by-step explanation:

Ozone is a secondary pollutant, that is, it is not emitted directly, but formed from other air pollutants, and highly oxidizing in the troposphere (lower layer of the atmosphere). Ozone is found naturally in the stratosphere (layer located between 15 and 50 km in altitude), where it has the positive function of absorbing solar radiation, preventing most of the ultraviolet rays from reaching the Earth's surface.

The formation of tropospheric ozone occurs through complex chemical reactions that take place between nitrogen dioxide and volatile organic compounds, in the presence of solar radiation. These pollutants are emitted mainly in the burning of fossil fuels, fuel volatilization, animal husbandry and in agriculture.