Physc 110 exam QUESTIONS AND
CORRECT ANSWERS 2024-2025
What three conditions do you need to form large deposits of coal?
Plants, stagnant water, sedimentary basin
What is the emitted pollutant from an ICE? What is the most deadly ICE pollutant?
-Carbon monoxide (CO), VOCs (volatile organic compounds), NOx (nitrogen oxygen
compounds)
-Carbon monoxide is the deadliest ICE pollutant
Why does carbon monoxide (CO) forms in an ICE? What could be done to
decrease CO formation during combustion?
-Incomplete combustion forms CO instead of CO2 (not high enough temperature
or oxygen levels)
-Increasing oxygen or increasing temperature can cause more combustion, which
can decrease CO formation
Explain the health problems that result when CO enters a body and reacts with
red blood cells.
-CO suffocates your red blood cells, which transfer oxygen through the body
-CO is 200 times more likely to hook to red blood cells than oxygen
What are VOCs? List the two ways VOCs are released into the environment when
using an ICE.
-Volatile organic compounds: hydrocarbons/unburned fuel; octane that didn't get
used in the combustion process
,-Fueling and uncombusted fuels are ways to release VOCs (develop smog/ozone)
Describe how NOx forms in an internal combustion engine. Explain the negative
health effects of exposure to NOx.
-NOx forms from the air brought in (nitrogen and oxygen react to form it)
-Negative effects include lung irritation and ozone pollutants
Describe the formation of Photochemical smog.
-Sun interacts with chemicals (pollutants out of tailpipes from the engine) in the
air, which is a secondary pollutant
-Smog is smoke + fog (unhealthy air event) made up of mainly ozone (O3)
Using simple chemical formulas, show how ozone, NO2, NO, and O2 are kept in
equilibrium in the absence of VOCs.
-First, NO2 + sunlight = NO + O
-Next, O + O2 = O3
-Last, NO +O3 = NO2 + O2 (this starts cycle over)
Describe how VOCs disrupt this equilibrium and lead to the formation of oxidants
and Photochemical Smog.
-VOCs react with NO from the NO + O to form PAN
-PAN doesn't let ozone break down, causing ozone pollutant levels to increase
(increases smog)
Review figure 6.11 in your text. What time of day and what time of year are ozone
levels the highest? Why?
-Afternoon and morning because sunlight is the highest during the day
-Summer because it has the highest temperatures during the year
What devices can be used to reduce the amount of CO and VOC emissions?
Explain how these measures result in an increase in NOx emissions.
-Carburetor, air cleaner, charcoal canister, EGR valve, catalytic converter, oxygen
sensor, manifold
, -High temperatures (caused from improved combustion through these devices)
increase NOx emissions
-Catalytic converter is a device which causes chemical reactions to take out NOx,
as well as leftover VOCs and CO
What three pollutants does a catalytic converter remove?
-NOx, VOCs, CO
-HC + O2 = CO2 + H2O (removes VOCs)
-CO + O2 = CO2 (removes CO)
-NOx = N2 + O2 (removes NOx)
Watch the London Killer Fog video. What was the significance of the London Smog
Disaster of 1952 to the modern environmental movement?
The Great Smog of London woke up the world to the dangers of unrestricted
pollution
How does "classic London smog" differ from photochemical smog? What are the
two key ingredients in "classic smog?" Hint: How did they come up with the name
smog.
-Smoke and fog
-Classic Smog: primary source pollutants (sulfur dioxide and particulate matter mix
with fog in the air to form gray industrial smog)
-Photochemical smog is caused by the material coming out of the tailpipes of cars.
Classical smog is entirely primary source pollutants.
Review Figure 6.9 in your text. Illustrate a temperature inversion using a graph of
temperature changes and altitude. Does a temperature inversion increase or
decrease levels of pollution beneath the inversion? Explain.
Pollution occurs below the inversion line but cannot go above it into the warmer
air (trapped on the surface)
What is particulate matter (PM)? Describe the effects of PM on human health and
the environment. Which type of PM is more dangerous, PM-10 or PM 2.5? Why?
CORRECT ANSWERS 2024-2025
What three conditions do you need to form large deposits of coal?
Plants, stagnant water, sedimentary basin
What is the emitted pollutant from an ICE? What is the most deadly ICE pollutant?
-Carbon monoxide (CO), VOCs (volatile organic compounds), NOx (nitrogen oxygen
compounds)
-Carbon monoxide is the deadliest ICE pollutant
Why does carbon monoxide (CO) forms in an ICE? What could be done to
decrease CO formation during combustion?
-Incomplete combustion forms CO instead of CO2 (not high enough temperature
or oxygen levels)
-Increasing oxygen or increasing temperature can cause more combustion, which
can decrease CO formation
Explain the health problems that result when CO enters a body and reacts with
red blood cells.
-CO suffocates your red blood cells, which transfer oxygen through the body
-CO is 200 times more likely to hook to red blood cells than oxygen
What are VOCs? List the two ways VOCs are released into the environment when
using an ICE.
-Volatile organic compounds: hydrocarbons/unburned fuel; octane that didn't get
used in the combustion process
,-Fueling and uncombusted fuels are ways to release VOCs (develop smog/ozone)
Describe how NOx forms in an internal combustion engine. Explain the negative
health effects of exposure to NOx.
-NOx forms from the air brought in (nitrogen and oxygen react to form it)
-Negative effects include lung irritation and ozone pollutants
Describe the formation of Photochemical smog.
-Sun interacts with chemicals (pollutants out of tailpipes from the engine) in the
air, which is a secondary pollutant
-Smog is smoke + fog (unhealthy air event) made up of mainly ozone (O3)
Using simple chemical formulas, show how ozone, NO2, NO, and O2 are kept in
equilibrium in the absence of VOCs.
-First, NO2 + sunlight = NO + O
-Next, O + O2 = O3
-Last, NO +O3 = NO2 + O2 (this starts cycle over)
Describe how VOCs disrupt this equilibrium and lead to the formation of oxidants
and Photochemical Smog.
-VOCs react with NO from the NO + O to form PAN
-PAN doesn't let ozone break down, causing ozone pollutant levels to increase
(increases smog)
Review figure 6.11 in your text. What time of day and what time of year are ozone
levels the highest? Why?
-Afternoon and morning because sunlight is the highest during the day
-Summer because it has the highest temperatures during the year
What devices can be used to reduce the amount of CO and VOC emissions?
Explain how these measures result in an increase in NOx emissions.
-Carburetor, air cleaner, charcoal canister, EGR valve, catalytic converter, oxygen
sensor, manifold
, -High temperatures (caused from improved combustion through these devices)
increase NOx emissions
-Catalytic converter is a device which causes chemical reactions to take out NOx,
as well as leftover VOCs and CO
What three pollutants does a catalytic converter remove?
-NOx, VOCs, CO
-HC + O2 = CO2 + H2O (removes VOCs)
-CO + O2 = CO2 (removes CO)
-NOx = N2 + O2 (removes NOx)
Watch the London Killer Fog video. What was the significance of the London Smog
Disaster of 1952 to the modern environmental movement?
The Great Smog of London woke up the world to the dangers of unrestricted
pollution
How does "classic London smog" differ from photochemical smog? What are the
two key ingredients in "classic smog?" Hint: How did they come up with the name
smog.
-Smoke and fog
-Classic Smog: primary source pollutants (sulfur dioxide and particulate matter mix
with fog in the air to form gray industrial smog)
-Photochemical smog is caused by the material coming out of the tailpipes of cars.
Classical smog is entirely primary source pollutants.
Review Figure 6.9 in your text. Illustrate a temperature inversion using a graph of
temperature changes and altitude. Does a temperature inversion increase or
decrease levels of pollution beneath the inversion? Explain.
Pollution occurs below the inversion line but cannot go above it into the warmer
air (trapped on the surface)
What is particulate matter (PM)? Describe the effects of PM on human health and
the environment. Which type of PM is more dangerous, PM-10 or PM 2.5? Why?
