Unit C Section 2.2

nitrogen (78%) oxygen (21%), argon (less than 1%), carbon dioxide (0.03%), traces of hydrogen and neon.

• by measuring the levels of pollutants in the air * by estimating the amount of emissions from pollution sources

Measuring the amounts of chemicals in the air is more accurate. -Measurements of chemicals in the air include chemicals produced by natural sources such as forest fires. • This provides a more complete picture of air quality • Monitoring chemicals in the air over a period of many years provides information about seasonal variations, as well as long-term trends.

Sulfur dioxide (SO2(g)) is a major air pollutant

Smog and Acid rain

It can affect your respiratory system (throat and lungs) and irritate your eyes.

• Sulfur dioxide and other oxides of sulfur form when oxygen combines with sulfur • The major source of sulfur dioxide is industrial processes. • In Alberta, the major source of sulfur dioxide is the oil and gas industry. • Sulfur dioxide and other oxides of sulfur are also formed by burning fuels such as coal, oil, and natural gas.

Industrial and electrical generating plants use devices called “scrubbers” to reduce sulfur dioxide emissions by up to 99%.

-Scrubbers use limestone (calcium carbonate) to convert the pollutant sulfur dioxide into a useful product. -The sulfur dioxide reacts with the calcium carbonate in the scrubber to produce gypsum (calcium sulfate). The gypsum is recovered and can be used in manufacturing.

sulfur dioxide + water + limestone + oxygen → gypsum + carbon dioxide

it can also be indoors, For example, a smoke-filled the party room can be a health hazard. Other substances that contribute to indoor air pollution include paints, glues, and cleaning supplies.

Nitrogen oxides (NOx(g)) are also major air pollutants

smog and acid rain

They affect the respiratory system and eyes.

The “x” in the chemical formula NOx(g) indicates that nitrogen oxides are mixtures of NO(g) and NO2(g) and sometimes other oxides of nitrogen.

• mainly from combustion in vehicles. • also form by combustion in generating plants • industrial processes, such as oil refining.

• The nitrogen formed by burning fuels first combines with oxygen to form nitrogen monoxide gas (NO(g)). • then combines with oxygen in the atmosphere to form nitrogen dioxide (NO2(g)), a brownish gas.

the main concern is with pollution from vehicles.

Also a major air pollutant.

the silent killer because it is a colorless and odorless gas

-When chemicals containing carbon burn, they produce carbon dioxide or carbon monoxide. • Carbon monoxide (CO(g)) forms if there is not enough oxygen to produce carbon dioxide (CO2(g)). • If there is enough oxygen during combustion, carbon dioxide is produced

• from human activities is motor vehicles. • combustion of wood (e.g., fireplaces, wood stoves) • natural gas, • industrial processes, • airplanes, • cigarette smoking.

it can be a problem during the colder months when many people burn wood for heating.

If inhaled, carbon monoxide reduces the amount of oxygen carried by the blood. As a result, it can cause headaches, sleepiness, chest pains, brain damage, and death.