Photochemical Smog

How does NO2 change into photochemical oxidants and Ozone?

NO2 is divided into NO and O by sunlight. The O binds with O2 to form ozone, and VOCs bind with NO to form photochemical oxidants.

What are VOCs?

Carbon-based compounds that volatilize (evaporate) easily (makes them “smelly)

What are the sources of VOCs?

gas, formaldyhide, cleaning fluids, oil-based paints, conifer trees

how is Ozone harmful to the environment?

Respiratory irritant, Damaging to plant stomata, limits plant growth

What are the two factors in the creation of ozone and photochemical smog?

Sunlight and Warmth

How does warmth influence the formation of ozone and photochemical smog?

increased warmth speeds up the creation of Ozone and evaporation of VOCs

When does Ozone production peak?

In the afternoon because sunlight is most direct and NO2 emissions are highest

How does ozone levels drop to balance its production during the day?

O3 reacts with NO to form NO2 and O2

If there is No NO to react with Ozone during the night, what happens?

Ozone builds up, and it combines with photochemical oxidants to form photochemcial smog

Impact of smog on the environment?

* Reduces sunlight; limits photosynthesis
* Ozone damages plant stomata and irritates animal respiratory tracts.

Impacts of smog on humans?

* Respiratory irritant
* worsens asthma
* bronchitis
* COPD (Chronic obstructive pulmonary disease)
* irritates eyes

Impacts of smog on economy?

* Increased healthcare costs to treat smog-related health problems
* Lost productivity due to sick workers
* Decreased agriculture due to less sunlight for photosynthesis