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Chapter 20 Study Guide
Hannah James
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Ecosystem services: services provided by the environment that impact humans, mostly
positively
o The atmosphere blocks UV radiation from the earth’s surface
Air pollution: various chemicals added to the atmosphere by natural events or human
activities in high enough concentrations to be harmful
Primary air pollutant: harmful substance, such as soot or carbon monoxide, that is emitted
directly into the atmosphere
Secondary air pollutant: harmful substance formed in the atmosphere when a primary air
pollutant reacts with substances normally found in the atmosphere or with other air
pollutants
o Particulate matter- scatters or absorbs light
o Solid particulate matter
Major Classes of Air Pollutants
1. Nitrogen oxides- gases produced by the chemical interactions between nitrogen and
oxygen
a. Gains energy from combustion of fuels
b. Produces high heat
c. Asthma is a result
d. Greenhouse gases
e. Nitric oxide, nitrogen dioxide, nitrous oxide
2. Sulfur oxides- gases produced by the chemical interactions between sulfur and oxygen
a. Damage plants
b. Irritates respiratory tracts of humans
c. Sulfur dioxide, sulfur trioxide
3. Carbon oxides- gases carbon monoxide and carbon dioxide
a. Reduce blood’s ability to transport oxygen
b. Greenhouse gas
c. Global warming/climate change
4. Hydrocarbons- diverse group of organic compounds that contain only hydrogen and
carbon
a. Gases and liquids at room temperature
b. Cancer and respiratory tract infections
c. Global warming
d. Methane, benzene
5. Ozone- form of oxygen considered a pollutant in one part of the atmosphere but an
essential compound in another
a. Stratosphere: oxygen reacts of UV radiation to form ozone
i. CFC’s react with stratospheric ozone, breaking it down to molecular
oxygen
b. Troposphere: ozone is a human-made air pollutant
i. Secondary air pollutant that reacts with sunlight
ii. Photochemical smog
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iii. Reduces air visibility and health problems
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Hazardous air pollutants: air pollutants that are potentially harmful and may pose longterm health risks to people who live and work around chemical factories, incinerators, or
other facilities that produce them
Clean Air Act Amendments of 1990
Two main sources of primary air pollutants are: transportation and industries
o Stationary sources
Smog and industrial smog (urban air pollution)
Photochemical smog: a brownish-orange haze formed by chemical reactions involving
sunlight, nitrogen oxide, and hydrocarbons
Temperature inversion: a deviation from the normal temperature distribution in the
atmosphere, resulting in a layer of cold air temporarily trapped near the ground by a
warmer, upper layer
o Thermal inversion
Smog and air pollution are common in Los Angeles, California and Mexico City, Mexico
o Due to transportation, consumers, industries and aircraft
Emphysema: a disease in which the air sacs in the lungs become irreversibly distended,
decreasing the efficiency of respiration and causing breathlessness and wheezy breathing
Chronic bronchitis: a disease in which the air passages of the lungs become permanently
inflamed, causing breathlessness and chronic coughing
o Sulfur dioxide, particulate matter, carbon monoxide, and ozone
Scrubbers help control air pollutants
Clean Air Act: sets limits of specific air pollutants permitted in the US
Global distillation effect: the process in which volatile chemicals evaporate from land as
far away as the tropics and are transported by winds to higher latitudes, where they
condense and fall to the ground
Sick building syndrome: presence of air pollution inside office buildings that can cause
eye irritations, nausea, headaches, respiratory infections, depression and fatigue
Air pollutants are typically more present and more of a problem in developing nations
because of rapid industrial growth attempts
My chapter didn’t have a previous outline to work off of, so I created this one from scratch. I
tried to outline the main ideas because this chapter was really long and semi-redundant.