Environmental Science: Acid Rain and Air Pollution
What are the two major nitrogen oxides (NOx)
Nitric oxide (NO) and nitrogen dioxide (NO2)
Describe nitric oxide (NO)
Nitric oxide is a colorless and odorless gas
Describe nitrogen dioxide (NO2)
Nitrogen dioxide is a yellow-brown gas that gives smog it's color. It irritates the eyes and increases suseptability to infection
What is the normal pH of rain?
5.6
What is photchemical smog?
A mixture of primary and secondary pollutants formed in sunlight.
Why do emissions of sulfur dioxide and nitrogen oxides effect entire regions?
Acid deposition can be carried by wind for hundreds of miles. Taller smokestacks on power plants only increase this effect.
How are buildings affected by acid rain?
Acid eats away at buildings and monuments made of marble and limestone
How are aquatic systems affected by acid rain?
Acid rain has acidified thousands of lakes in northeastern US and Canada. The lower pH of water can kill algae, and fish and amphibian eggs. Furthermore, the acidity can leech heavy metals from rocks and soil suffocating fish.
How are humans affected by acid rain?
Acid rains can reduce food supply and damage our environment.
Describe the process by which photochemical smog is produced
In the atmosphere nitrogen oxide forms nitrogen dioxide. UV light breaks the nitrogen dioxide into nitrogen oxide and an atom of oxygen. The oxygen atom reacts with an oxygen molecule to form ozone.
Describe ozone (O3)
Ozone is a colorless gas with a slightly sweet odor. It is a strong oxidant and can crack rubber, cause lung damage and kill plants.
Describe particulates
Particulates are particles suspended in the air like smoke and dust. It is dangerous in high concentrations and fine paricles cn become embedded in lungs and cause cancers
Name the two types of stationary air pollution sources
Point (fixed point) and fugitive (open areas) sources
What influence do thermal inversions have on air pollution?
Pollution is prevents from rising by the layer of warmer air, trapping it around the city. Add pic
Describe emissions trading or banking as an air pollution solution
It attempts to use the market to decrease pollution. Industries and power plants are given a specific number of pollution credits to emit pollution. These credits can be used or sold.
What influence does precipitation have on air pollution?
It cleans the air of pollutants
What does acid depostion refer to?
It includes acidic rain, snow, fog and dry particulates
What effect does acid rain have on vegetation?
It weakens plants and trees making them more susceptible to disease. Additionally, acid levels affect soil nutrient levels.
What is industrial smog?
Typically made up of sulfur dioxide and particulates. It is produces during the winter in cities when coal is burned. Historically Chicago and London had high levels but, today it is largely confined to developing nations.
Where was asbestos historically used
In brake pads and insulation
What are the primary source of nitrogen oxides (NOx)?
Auto exhaust and power plants
Describe carbon monoxide (CO)
Carbon monoxide is a colorless and odorless gas. It is toxic because it binds to hemoglobin in your blood. Carbon monoxide can be taken up two hundred and fifty times faster than oxygen leading to asphyxiation.
How can smog from mobile sources be controlled?
Catalytic converters, smog checks (to ensure compliance), reformulation of gasoline, removal of older, more polluting vehicles, increased use of electrical vehicles, and use of carpool and mass transit
What are the primary source of sulfur dioxide (SO2)?
Coal burning power plants, volcanoes and sea spray
Hoe do electrostatic precipitators reduce pollution from smoke stacks?
Electrical currents remove particulates
Name three devices that can be installed on smokestacks to reduce pollution
Electrostatic precipitators, baghouse filters and wet scrubbers
Where is acid rain a major issue?
Europe, the Eastern US, Canada (emissions come from US) and China
How is acid rain formed?
Primary pollutants (SO2 and NOx) mix with water vapor to form secondary pollutants. Sulfur dioxide becomes sulfuric acid (H2SO4) and sulfate salts. Nitrogen oxides become nitric acid (HNO3) and nitrate salts. The acids precipitate out of atmosphere as acid deposition.
What is the difference between primary and secondary pollutants?
Primary pollutants are released directly into the air. Secondary pollutants are produced by reactions between primary pollutants and atmospheric compounds.
Name the two types of air pollution sources
Stationary and mobile sources
Name the two primary pollutants that cause acid rain
Sulfur dioxide (SO2) and nitrogen oxides (NOx)
Describe sulfur dioxide (SO2)
Sulfur dioxide is a colorless and odorless gas produced from burning coal. It leads to acid rain.
Name and describe three methods of reducing acid rain and it's effects
Sulfur levels in coal can be reduced by removing sulfur or gasifying coal (coal gasification). Wet scrubbers treat exhast gas with a water and lime mix. Limestone can reduce the pH of lakes.
What determines the sensitivity of a region to acid rain?
The buffering capacity of a region can be effected by the thickness of soil and limestone levels
Why might China become a major producer of acid rain?
They have large coal deposits and produce large numbers of coal fired plants
What influence do mountains have on air pollution?
They reduce the flow of air. As a result pollution builds up in adjacent low lying areas.
Hoe do baghouse filters reduce pollution from smoke stacks?
They trap pollutants