Chapter 15 Air Pollution

What is a scrubber?

It uses a combination of water and air that separates and removes particles.

What is lead

Lead(Pb) is a trace metal that occurs naturally in rocks and soil.

What is Mercury?

Mercury (Hg) is a trace metal that is found in coal and oil, and is toxic to the central nervous system of humans and other organisms.

What are the primary anthropogenic sources of nitrogen oxdies

Motor vehicles, and stationary fossil fuel combustion

How are nitrogen oxides produced?

Much of the atmosphere is made up of nitrogen gas (N2) and therefore all combustion leads to the formation of some nitrogen oxides.

What is Nitrogen dioxide?

Nitrogen dioxide (NO2) is a pungent, reddish-brown gas

What is nitrogen oxide?

Nitrogen oxide (NO) is a colorless, odorless gas

What do lightning strikes create ?

Nitrogen oxides

Explain the formation of acid deposition.

Nitrogen oxides and sulfur dioxide are released into the atmosphere naturally and anthropogenically. In the presence of oxygen water, they are transformed into nitric acid and sulfuric acid. Those compounds break down further producing nitrate, sulfate, and hydrogen ions (H+)

Give an example of a secondary pollutant.

Ozone, Sulfate(SO4) and nitrate(NO3)

What kind of air pollution is a concern?

Particles smaller than 10 um

What are photochemical oxidants?

Photochemical oxidants are a class of air pollutants formed as a result of sunlight acting on compounds such as nitrogen oxides and and sulfur dioxide.

How is sulfur dioxide formed?

Plants and animals contain sulfur. Therefore, when the fossil fuels that derive from them are combusted, the sulfur combines with oxygen to form sulfur dioxide.

What does air pollution refer to?

Pollution in the troposphere (first 16 km of the atmosphere)

What are primary pollutants?

Primary pollutants are polluting compounds that come directly out of the smokestack , exhaust pipe, or natural emission source.

What is smog?

Smog is the mixture of oxidants and particulate matter.

What are the main components of acid deposition?

Sulfate(SO4) and nitrate(NO3)

What is sulfur dioxide?

Sulfur dioxide (SO2) is a corrosive gas that comes primarily from the combustion of fuels such as coal and oil.

What are the six major pollutants that harm humans and the environment?

Sulfur dioxide, nitrogen oxides, carbon monoxide, particulate matter, tropospheric ozone, and lead.

What is the largest uncontrolled source of mercury?

The largest uncontrolled source of mercury is coal-fired electricity generation plants.

Explain how ozone is formed.

The process must take place in the day when there is sunlight. If there is an abundance of nitrogen oxides but few VOCs, ozone (O3) forms. When the sunlight is gone, ozone breaks down. This process will happen throughout the day with small amounts of photochemical smog formation.

What is thermal inversion?

Thermal inversion is when is when a relatively warm layer of air traps covers a layer of cold dense air.

What are secondary pollutants?

They are primary pollutants that have undergone transformation in the presence of sunlight, water, oxygen, or other compounds.

How harmful are UV-B and UV-C rays?

They have enough energy to cause potentially significant damage to the tissues and and DNA of living organisms.

How harmful are UV-A Rays?

They have the potential of passing through the atmosphere without being absorbed, and can possibly initiate skin cancer.

What are electrostatic precipitators?

They use an electrical charge to make particles come together so they can be removed.

What is the largest source of carbon monoxide and nitrogen oxides?

Transportation

What are volatile organic compounds?

VOCs are hydrocarbons-compounds that contain carbon-hydrogen bonds, such as gasoline, lighter fluid, and perfumes.

What do volcanoes release?

Volcanoes release sulfur dioxide, particulate matter, carbon monoxide, and nitrogen oxides.

Where does air pollution occur naturally from?

Volcanoes, fires

Explain how photochemical smog is formed.

When VOCs are present they combine with nitrogen oxide. Nitrogen oxide is not able to break down ozone by recombining with it, therefore a large amount of ozone accumulates.

Give examples of primary pollutants.

CO, CO2, SO2, NOx, suspended matter, and many VOCs.

What is carbon dioxide?

Carbon dioxide is a colorless, odorless gas that is formed during the complete combustion of most matter, including fossil fuels and biomass.

What is carbon monoxide?

Carbon monoxide (CO) is a colorless, odorless gas that is formed during incomplete combustion of most matter, and is a common emission in vehicle exhaust.

What is the major anthropogenic source of sulfur dioxide?

Electricity generation

What is fluidized bed combustion?

It is a technique used to remove sulfur dioxide from coal exhaust during combustion. It is a process in which granulated coal is burned in close proximity to calcium carbonate, which reduces sulfur dioxide emissions.

Where does particulate matter come from?

It comes from the combustion of wood, animal manure, and other biofuels, coal, oil, and gasoline.

What are the effects of sulfur dioxide?

It is a respiratory irritant and can badly affect plant tissue

What is particulate matter?

It is solid or liquid particles suspended in air.

Where is air pollution primarily a health threat?

Asia, Africa, and South America

How can nitrogen oxide emissions be reduced?

Burn temperatures must be reduced and the amount of oxygen miat be reduced.

What is an inversion layer?

An inversion layer is a layer that traps emissions that accumulate beneath it

How many deaths are there world wide from air pollution?

1.6 million

What percentage of sulfur dioxide emission are natural ?

30 percent

What percentage of nitrogen oxide emissions are natural?

44 percent

What percentage is the atmosphere nitrogen gas?

78%

What percentage of volatile organic compound emissions are natural?

89 percent

What is a persistent source of lead?

A persistent source of lead is lead based paint, which an be toxic on the central nervous system.

What are fabric filters?

Fabric filters are a type of filtration device that allow gases to pass through them but remove particulate matter.

Explain the formation and breakdown of stratospheric ozone.

First, UV-C radiation breaks the bonds holding together the oxygen molecule (O2) leaving two free oxygen atoms. In the presence of ultraviolet radiation, oxygen is converted to ozone. Each cycle absorbs UV energy.

What are natural sources of nitrogen oxides?

Forest fires, lightning, and microbial action in soils

From what is particulate matter released?

From diesel powered vehicles, road dust, rock-crushing operations, volcanoes, forest fires, and dust storms.

How is sulfur dioxide released naturally?

From volcanic eruptions and forest fires

What countries are part of the black triangle ?

Germany, Poland, and the Czech Republic

What's the simplest removal method of particulate matter?

Gravitational settling, which relies on gravity to remove particles.

How is haze created?

Haze is caused when particulate matter from air pollution scatters light.

Why is carbon monoxide dangerous?

It can be a dangerous indoor air pollutant when exhaust system on natural gas heaters malfunction