Name __________________
Air pollution: carbon monoxide & dioxide lab
What’s in the Air?
Air is a mixture of gases surrounding the planet that is retained by the Earth's gravity. It contains roughly 78.08%
nitrogen, 20.95% oxygen, 0.93% argon, 0.038% carbon dioxide, trace amounts of other gases, and a variable amount
(average around 1%) of water vapor. Air also contains many small particles that are suspended (such as dust).
Air pollution occurs when human activities add abnormal amounts of gases or particles into the air. The severity of
air pollution in a given area depends on several factors, including climate, topography, population density, and the
number and type of industrial activities. Some of the most common kinds of air pollution includes: particle pollution
(often referred to as particulate matter), ground-level ozone (producing smog), carbon monoxide, sulfur oxides
(producing acid rain), nitrogen oxides, and lead.
These pollutants can harm your health and the environment, and cause property damage. It is important to realize
that in most cases air pollution is invisible. Sophisticated equipment is required to test your air for pollution.
Human health effects
Air pollution most often affects our respiratory (lung) function. Smog is a reactive gas that attacks lung tissue and
burns the eyes. Soot and other particles become embedded in the lungs and leads to chronic coughing and lung
damage. Carbon monoxide is a deadly odorless and colorless gas that will produce death in a few minutes in high
concentrations.
Lung capacity exercise
Your exposure to air pollution is obviously correlated to the amount (volume) of air that you breathe. The average
human lung holds about 6 liters = 6000 cubic centimeters of air.
1) Blow up a balloon. What is the volume of air in there? Estimate this by considering the balloon to be a sphere.
The volume of a sphere = 4.2(radius3). You can estimate the radius as: radius = circumference/6.28 (use a string to
measure the circumference of the balloon and then measure the length of the string with a rule). Make sure you
measure in centimeters!
Volume of balloon = __________ cubic cm
What percentage of your total lung capacity is this?
How many times larger is your lung volume than this balloon?
The amount of air you actually breathe is how much flows in and out of your lungs. The average adult at rest inhales
and exhales about 8 liters of air per minute. That totals something like 11,000 liters of air in a day.
2) If there are 0.26 gallons in a liter, how many gallons of air do you breathe in a day?
SHOW WORK:
3) Get a plastic bag and ask the instructor what is the volume of that bag. Time yourself: Pinch the end and breathe
into the bag until it is almost fully inflated. Measure how much time it takes to inflate the bag:
_______seconds to inflate the bag so: _______bag volume/seconds = ____________ gallons/second
This converts to:
________ gallons/second x 86400 seconds (per day) = ___________ gallons per day
If you did this for 24 hours, how many gallons of air would you breathe in and out of your lungs?
Is this number similar to the gallons per day you calculated for #2 above?
Why or why not is your estimate from this exercise different?
Cars! Smog & Carbon Monoxide
The air in Charlotte is, at times, some of the worst in the nation. The main reason is smog ( smoke + fog). Smog is a
chemical mixture of gases that commonly forms a brownish-yellow haze in the air, primarily over urban areas.
Urban smog is mainly emitted from cars and trucks, from the combustion of hydrocarbon fuels. Components of
smog include ozone (O3), nitrogen oxides (NOx), volatile organic compounds (VOC), sulfur dioxide (SO2), and
particulate matter. These gases result from a photochemical reaction between certain airborne pollutants and strong
sunlight. Smog is most prevalent in the summer months, when there is the most sunlight and temperatures are the
highest. Smog poses a significant threat to animal, plant, and human life in fact, thousands die every year as a result
of this pollution.
In complete combustion, hydrocarbon (HC) is oxidized (with O2) to produce only CO2 + H2O:
HC + O2 CO2 + H2O
Carbon monoxide (CO) is produced by the incomplete combustion of any fuel that contains carbon. In this case
some of the CO is not fully oxidized to CO2:
HC + O2 CO2 + H2O + CO
This includes gasoline, natural gas, oil and propane, as well as coal and wood products. In the home, sources of
carbon monoxide include gas and oil burning appliances like furnaces, ovens, wood burning stoves, and charcoal
grills.
In automobiles, CO is produced when you have an older car that is inefficiently burning gasoline. For example if
your car is not well tuned or has a broken catalytic converter. Very new cars have very efficient catalytic converters
and with computers that closely regulate combustion to produce almost zero CO.
Carbon monoxide (CO) is an odorless, colorless, tasteless gas that is slightly lighter than air. It is sometimes called
exhaust gas.. Under high pressure it becomes a liquid. It can also kill within minutes in high concentrations. 3
Calculation:
The US has more cars than people! The average American spends almost 2 hours per day in a car, driving around. If
you live to be 70 years old, how many years of your life will you spend sitting in a car? SHOW WORK
Carbon Dioxide Analysis
1) How many cars/passenger trucks/18-wheelers/delivery trucks (on average) pass by the North Meck HS in an hour?
How many cars/passenger trucks/18-wheelers/delivery trucks pass by the school in 8 hours?
How many busses pass by the school in an hour?
Estimate how many people are on the bus.
2) Assume that a car passing by is going about 30 miles per hour. Assume it gets 20 miles per gallon of gasoline.
How many gallons of gasoline will that car burn in an hour? SHOW WORK
3) CO2 is the main cause of global warming. Each gallon of gasoline that is burned releases about 19 gallons of CO2
into the atmosphere. How can 1 gallon of liquid fuel release 19 gallons of gas? Explain
4) Calculate how many gallons of CO2 is released by all the cars passing by the North Meck in 8 hours if they each
drive 50 miles and they each get 20 miles per gallon of gasoline. SHOW WORK.
Now do the same for passenger trucks assuming they are getting 15 miles per gallon.
5) The Interstate in Charlotte has about 150,000 cars per day. How much CO2 is released by those cars if they each
drive 200 miles and they each get 20 miles per gallon of gasoline? SHOW WORK.
6) City buses get about 5 miles per gallon of gasoline. How many people need to ride the bus to save gasoline in
comparison to driving a car that gets 20 miles per gallon? SHOW WORK
In the space below, make a graphical comparison of the carbon footprint for a person driving alone in a car, truck,
and bus. Use the assumptions or averages above for gas mileage and occupancy. All representations must have a
scale or quantifiable value.