Question

Photochemical smog consists of excessive amounts of X in addition to aldehydes, ketones, PAN etc. X is:
A. methane
B. carbon monoxide
C. carbon dioxide
D. ozone

Answer 1

Hint: Photochemical smog is called summer smog because during summer when temperature is warmer and there is more sunlight present and hence Photochemical smog is the dominant type of smog formation. The X molecule is formed by three types of the same atoms. The atom in X has an atomic number of 8 and it belongs to the period 2 and group 16 of the periodic table.

Complete step by step answer:
- Basically photochemical smog is formed by the chemical reaction of sunlight. It is formed when the U.V radiation has high concentration in the atmosphere, it combines with the ozone gases and nitrogen gases ($N{{O}_{x}}$) and smog is formed.

- Photochemical smog basically depends on primary pollutants and also on the formation of secondary pollutants. The primary pollutants are nitrogen oxides, particularly nitrogen dioxide, nitrogen oxides and various volatile organic compounds.
- This includes PAN ( peroxyacyl nitrates ), ozone and aldehydes.

- All of these chemicals are usually highly oxidizing and reactive. Is therefore considered to be a problem of industrialisation. As it travels with the wind, it can affect the populated areas also.
 - Hence, we can say that the correct option is (D), that is photochemical smog consists of excessive amounts of Ozone in addition to aldehydes, ketones, PAN etc.
So, the correct answer is “Option D”.

Note: - It is found that photochemical smog is capable of influencing irreversible damage on the heart and lungs. Even a short-term exposure to it can have ill effects.
- We can control it by planting various plants like Pinus, Pyrus and Vitis, as these plants are found to have the capability to metabolize nitrogen dioxide.