Transcript 2.5-Air-Pollution-Basics

Please take out your Module 46 reading assignment
Module 46
 Double-check your chart with mine
 Check your multiple choice
1. C
2. B
3. D
4. A
5. E
Energy Test Results
Multiple Choice
Short Answer
A = 31.5
B = 28
C = 24.5- 27.5
D = 21-24
A = 9-10
B = 8-9
C = 7-8
D = 6-7
Retakes for scores of 24 and
below must be done by next
Friday.
Retakes for scores of 6.5 and
below
Energy Test Corrections
1. Re-do FRQ parts that were incorrect
2. For each multiple choice, write the down the
major/concept or definition that you missed. These
can overlap.
3. These are due next Friday if you don’t finish them
today.
4. Done? Move on to book notes on modules 47-48, with
multiple choice!
Air Pollution
 Air pollutants come from three sources:
 Mobile (cars)
 Stationary (factories)
 Natural (volcanoes, animals)
 Due to gravity, pollutants tend to stay near in the
troposphere (lowest layer of atmosphere)
Primary Air Pollutants
 Primary pollutants: materials released into the
atmosphere in unmodified forms
 Carbon Oxides (CO and CO2)
 Nitrogen Oxides (NO, NO2)
 Particulates
 Sulfur Dioxide (SO2)
 VOC’s
 CFC’s
 Secondary pollutants: materials created when
primary pollutants, sun and/or water mix
Carbon Monoxide (CO)
 Colorless, odorless, toxic gas formed by incomplete
burning of carbon compounds
 Sources: car exhaust, burning wood, tobacco smoke
 CO attaches to hemoglobin, a protein in red blood cells
that carries oxygen
 After several hours of exposure, red blood cells no longer
carry oxygen, causing death
Carbon Dioxide (CO2)
 Colorless, odorless gas
 93% of CO2 in troposphere is from natural carbon
cycle; 7% from human activity
 Burning of fossil fuels like oil, natural gas, coal
 Burning of forests and grasslands
Major cause of climate change (rise of atmospheric
temperatures since the Industrial Revolution)
Nitrogen Oxides (NO and NO2)
 Combustion in factories and car engines give off NO
(nitrogen oxide)
 NO combines with O2 in air to make NO2 (nitrogen
dioxide), a reddish brown gas
 Both nitrogen oxides are major contributors to smog
Particulates
 Particulates = tiny pieces of solid materials floating in
atmosphere
 From burning fossil fuels, building demolition, fires,
industrial plants giving off ash
 Can be carcinogenic (cancer causing), and can prevent
lungs from exchanging CO2 and O2
 Prolonged exposure is key: asbestos, mining, etc.
Sulfur Dioxide (SO2)
 Colorless gas that smells like rotten eggs
 1/3 comes from natural sulfur cycle
 2/3 comes from human activities
 Burning of coal
 Refining of crude oil
Can cause breathing problems
Can form H2SO4 (sulfuric acid) when it combines with
water vapor in atmosphere
Volatile Organic Compounds (VOC’s)
 Organic compounds that exist as gases in the air
 Ex: CH4 (methane), C6H6 (benzene)
 1/3 from natural causes; 2/3 from human activity
 Landfills, cows, industrial solvents, car and power plant
emissions, tobacco smoke
 Methane contributes to climate change; Benzene
can cause leukemia, blood disorders, and immune
system damage
Chlorofluorocarbons (CFC’s)
 CFC’s (also called freons) are odorlesss, colorless, and
non-toxic
 Used as coolants in refrigerators, cleaners, propellants
for aerosol products
 Break down into reactive chlorine, flourine, and
bromine atoms in the stratosphere, breaking down the
ozone layer
Visualizing Air Pollution
 Today: firm up your general knowledge of types and
sources of air pollution
 Next week: look specifically at photochemical smog,
acid rain