air pollution

primary pollutants

Primary pollutants enter the air directly. Some are released by natural processes, like ash from volcanoes. Most are released by human activities. They pour into the air from vehicles and smokestacks. Several of these pollutants are described below. Carbon oxides include carbon monoxide (CO) and carbon dioxide (CO2 ). Carbon oxides are released when fossil fuels burn. Nitrogen oxides include nitric oxide (NO) and nitrogen dioxide (NO2 ). Nitrogen oxides form when nitrogen and oxygen combine at high temperatures. This occurs in hot exhausts from vehicles, factories, and power plants. Sulfur oxides include sulfur dioxide (SO2 ) and sulfur trioxide (SO3 ). Sulfur oxides are produced when sulfur and oxygen combine. This happens when coal burns. Coal can contain up to 10 percent sulfur. Toxic heavy metals include mercury and lead. Mercury is used in some industrial processes. It is also found in fluorescent light bulbs. Lead was once widely used in gasoline, paint, and pipes. It is still found in some products. Volatile organic compounds (VOCs) are carbon compounds such as methane. VOCs are released in many human activities, such as raising livestock. Livestock wastes produce a lot of methane. Particulates are solid particles. These particles may be ash, dust, or even animal wastes. Many are released when fossil fuels burn (see Figure 22.1).

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secondary pollutants

Secondary pollutants form when primary pollutants undergo chemical reactions after they are released. Many occur as part of photochemical smog. This type of smog is seen as a brown haze in the air. Photochemical smog forms when certain pollutants react together in the presence of sunlight. You can see smog hanging in the air over San Francisco in Figure 22.2. Photochemical smog consists mainly of ozone (O3 ). The ozone in smog is the same compound as the ozone in the ozone layer,(O3 ). But ozone in smog is found near the ground. Figure 22.3 shows how it forms. When nitrogen oxides and VOCs are heated by the Sun, they lose oxygen atoms. The oxygen atoms combine with molecules of oxygen to form ozone. Smog ozone is harmful to humans and other living things.

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the clean air act

By 1970, it was clear that something needed to be done to protect air quality. In the U.S., the Clean Air Act was passed. It limits what can be released into the air. As a result, the air in the U.S. is much cleaner now than it was 50 years ago. But air pollution has not gone away. Vehicles, factories, and power plants still release more than 150 million tons of pollutants into the air each year.

types of air pollutants

There are two basic types of pollutants in air. They are known as primary pollutants and secondary pollutants.

the big smoke

By the mid-1900s, air quality in many big cities was very bad. The worst incident came in December 1952. A temperature inversion over London, England, kept cold air and pollutants near the ground. The air became so polluted that thousands of people died in just a few days. This event was called the Big Smoke.

air pollution in the u.s.

At the same time, many U.S. cities had air pollution problems. Some of the worst were in California. Cars were becoming more popular. Oil refineries and power plants also polluted the air. Mountain ranges trapped polluted air over cities. The California sunshine caused chemical reactions among the pollutants. These reactions produced many more harmful compounds.

air quality

Air quality is a measure of the pollutants in the air. More pollutants mean poorer air quality. Air quality, in turn, depends on many factors. Some natural processes add pollutants to the air. For example, forest fires and volcanoes add carbon dioxide and soot. In dry areas, the air often contains dust. However, human actions cause the most air pollution. The single biggest cause is fossil fuel burning.

the industrial revolution

Poor air quality started to become a serious problem after the Industrial Revolution. The machines in factories burned coal. This released a lot of pollutants into the air. After 1900, motor vehicles became common. Cars and trucks burn gasoline, which adds greatly to air pollution.

evaporation of vocs

VOCs enter the air by evaporation. VOCs are found in many products, like paints and petroleum products. Methane is a VOC that evaporates from livestock waste and landfills.

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burning forests

Millions of acres of forest have been cut and burned to make way for farming. Figure 22.4 shows an example. Burning trees produces most of the same pollutants as burning fossil fuels.

burning fossil fuels

Burning fossil fuels releases many pollutants into the air. These pollutants include carbon monoxide, carbon dioxide, nitrogen dioxide, and sulfur dioxide. Motor vehicles account for almost half of fossil fuel use. Most vehicles run on gasoline, which comes from petroleum. Power plants and factories account for more than a quarter of fossil fuel use. Power plants burn fossil fuels to generate electricity. Factories burn fossil fuels to power machines. Homes and other buildings also burn fossil fuels. The energy they release is used for heating, cooking, and other purposes.

sources of air pollution

Most pollutants enter the air when fossil fuels burn. Some are released when forests burn. Others evaporate into the air.

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instructional diagrams

description_image

This diagram shows the natural ozone destruction. It consists in 3 steps, the first one occurs when the uv radiation shocks the ozone molecule and this one gets divided into the oxygen molecule and the oxygen atom. Then, the ozone molecule is added to the oxygen atom getting as result those oxygen molecules.

questions

type of pollutant that forms when other pollutants undergo chemical reactions

a. air quality

b. photochemical smog

c. primary pollutant

d. VOC

e. particulate

f. ozone

-->  g. secondary pollutant

Many of the smoggiest cities are in which state?

-->  a. California

b. New York

c. Texas

d. Florida

primary pollutant that is a carbon compound such as methane

a. air quality

b. photochemical smog

c. primary pollutant

-->  d. VOC

e. particulate

f. ozone

g. secondary pollutant

Slash-and-burn is done primarily

a. for energy

-->  b. to clear land for agriculture

c. to clear land for construction

d. none of these

type of pollutant that enters the air directly

a. air quality

b. photochemical smog

-->  c. primary pollutant

d. VOC

e. particulate

f. ozone

g. secondary pollutant

How many pollutants does the Clean Air Act of 1970 regulate?

a. 6

b. 89

-->  c. 189

d. 289

Pollutants may collect

a. beside mountain ranges

b. in inversions

c. when there is little wind

-->  d. all of these.

solid particle in the air

a. air quality

b. photochemical smog

c. primary pollutant

d. VOC

-->  e. particulate

f. ozone

g. secondary pollutant

measure of the pollutants in air

-->  a. air quality

b. photochemical smog

c. primary pollutant

d. VOC

e. particulate

f. ozone

g. secondary pollutant

Smog that forms from a reaction with sunlight is known as

a. photographic smog

-->  b. photochemical smog

c. photosynthesized smog

d. photogenic smog

brown haze that forms in air when certain pollutants react together in sunlight

a. air quality

-->  b. photochemical smog

c. primary pollutant

d. VOC

e. particulate

f. ozone

g. secondary pollutant

primary component of photochemical smog

a. air quality

b. photochemical smog

c. primary pollutant

d. VOC

e. particulate

-->  f. ozone

g. secondary pollutant

Before the Industrial Revolution there was very little air pollution that wasnt natural.

-->  a. true

b. false

Burning fossil fuels releases carbon dioxide into the atmosphere.

-->  a. true

b. false

About 150 million tons of pollutants enter into the atmosphere every year.

-->  a. true

b. false

The Clean Air Act regulates carbon dioxide.

a. true

-->  b. false

Ozone in the lower atmosphere protects life from UV radiation.

a. true

-->  b. false

The worst air pollution in the U.S. occurs in

a. New York State.

b. New Jersey.

-->  c. California.

d. Florida.

The Big Smoke was an incident of deadly air pollution that occurred in the mid-1900s in

a. Los Angeles.

b. San Francisco.

c. Mexico City.

-->  d. London.

In the U.S. today, air pollution comes from

a. vehicles.

b. factories.

c. power plants.

-->  d. all of the above

Most primary pollutants are released by

a. volcanic eruptions.

b. natural processes.

-->  c. human activities.

d. forest fires.

Pollutants released into the air when fossil fuels burn include

a. carbon monoxide.

b. carbon dioxide.

c. particulates.

-->  d. all of the above

Smog consists mainly of

a. smoke.

b. particulates.

c. water vapor.

-->  d. none of the above

Almost half of the fossil fuels that are burned are used by

a. factories.

b. power plants.

-->  c. cars and trucks.

d. homes and other buildings.

Air pollution is caused completely by human actions.

a. true

-->  b. false

The air in the U.S. is more polluted now than it was 50 years ago.

a. true

-->  b. false

Livestock wastes pollute the air with methane.

-->  a. true

b. false

Animal wastes add particulates to the atmosphere.

-->  a. true

b. false

Particulates include only particles big enough to be seen by the unaided eye.

a. true

-->  b. false

Ozone forms when certain air pollutants are heated by direct sunlight.

-->  a. true

b. false

Paints and petroleum products release volatile organic compounds.

-->  a. true

b. false

Air pollution contributes to global warming.

-->  a. true

b. false

In California, mountain ranges can trap polluted air over cities.

-->  a. true

b. false

All primary pollutants come from directly from motor vehicles and smokestacks.

a. true

-->  b. false

diagram questions

question_image

What produces ozone?

a. Sun

-->  b. Oxygen

c. Hydrogen

d. Carbon

question_image

How many times does the sun appear in the image?

-->  a. 1

b. 2

c. 3

d. 4

question_image

After energy is applied to the oxygen molecule, what happens?

-->  a. Splits into 2 Oxygen atoms

b. Multiplies into 3 ozone atoms

c. Splits into 2 ozone molecule

d. Splits into 2 oxygen molecules

question_image

What are the elements in an Oxygen atom?

a. Oxygen molecule

b. Energy

c. Ozone molecule

-->  d. Neutron, Electron, Proton

question_image

From how many differently named parts does the Oxygen atom consist of?

a. 2

b. 5

-->  c. 3

d. 4

question_image

How many types of atom are shown in the picture?

-->  a. 3

b. 4

c. 5

d. 2

question_image

Where do VOCs come from?

a. Radios

b. Hairspray

c. Televisions

-->  d. Landfills

question_image

How many atoms of Oxygen are present in an Ozone molecule?

a. 2

b. 1

-->  c. 3

d. 4

question_image

UV radiation splits oxygen molecule into how many oxygen atoms?

a. 3

b. 4

-->  c. 2

d. 5

question_image

What comes out when UV radiation hits oxygen molecules?

a. ozone molecule

-->  b. oxygen atoms

c. hydrogen atoms

d. helium atoms

question_image

In which step is ozone formed?

a. Step 5

-->  b. Step 3

c. Step 2

d. Step 1

question_image

What is required to split an oxygen molecule?

a. O1

b. Ozone

c. oxidation

-->  d. Applied energy

question_image

How many steps are there in the oxygen-ozone cycle?

a. 2

-->  b. 5

c. 3

d. 6

question_image

How many steps does the Oxygen-Ozone-Oxygen cycle have?

-->  a. 5

b. 4

c. 3

d. 2

question_image

How is Ozone (O3) formed?

-->  a. The Oxygen Molecule is split by electrical discharge

b. by smashing atoms together in machines known as particle accelerators

c. energised particles such as neutrinos and protons are released

d.  neutrons collide with the common isotope of uranium

question_image

What is the first thing that happens to the oxygen molecule?

a. ozone performing oxidation and decomposition functions

b. activated ozone

-->  c. The oxygen molecule is split by electrical discharge

d. ozone is formed

question_image

How many changes does an Oxygen molecule go through to become Activated Ozone?

-->  a. 4

b. 2

c. 1

d. 3

question_image

What happens after the oxygen molecule is split by electrical discharge?

a. ozone oxidates

b. ozone decomposes

-->  c. ozone is formed

d. ozone activates

question_image

What is formed after oxygen molecule is split by electrical discharge?

a. Carbon Dioxide

b. Oxygen

c. Nitrogen

-->  d. Ozone