Question

Photochemical smog does not contain________
a. PAN
b. Ozone
c. Nitrogen dioxide
d. $S{O_2}$

Answer 1

Hint: Photochemical smog contributes to the main constituent of the environmental pollution, this is caused by photochemical reactions which occur when the reaction is caused by the absorption of energy in the form of light. It most commonly takes place inside the summertime.

Complete answer:
The absorption of energy in the form of light from the energy-giving sources, the chemical reactions in presence of light taking place forms to photochemical smog

Photochemical smog's largest contributor is cars, even as coal-fired power plant life and some other strength vegetation additionally produce the necessary pollution to facilitate its manufacturing. Due to its abundance in regions of warmer temperatures, photochemical smog is most commonplace inside the summertime

Nitric oxide $(NO)$ and nitrogen dioxide $(N{O_2})$ are emitted from the combustion of fossil fuels, together with being naturally emitted from matters consisting of volcanoes and woodland fires (it's miles the significant awareness of those pollutants inside cities this is of the most situation but, as natural emissions tend to spread out over larger regions). When uncovered to ultraviolet radiation, $N{O_2}$ is going through a complicated collection of reactions with hydrocarbons to produce the additives of photochemical smog—a combination of ozone, nitric acid, aldehydes, peroxy acyl nitrates (PANs) and other secondary pollutants.

$N{O_2}$, ozone and PANs are referred to as photochemical oxidants because they could react and oxidize positive compounds in the surroundings or inside someone's lungs that aren't generally oxidized. Even small lines of those chemical substances can have an effect on the respiratory tract of human beings and animals, and damage crops and trees.

Hence, the correct answer is option (D).

Note: Photochemical smog has an adverse effect on the human body when smog is inhaled it causes respiratory disease, can worsen the asthma condition and makes it difficult to breathe. When naked eye comes in contact with the smog it causes various problems like eye irritation, redness of the eye, etc.