Atmospheric Pollution and Air Composition

Questions and Answers

Which gas is the most abundant component in the Earth's atmosphere?

Nitrogen

What is the main source of Carbon Monoxide pollution in the atmosphere?

Combustion processes

What are the main constituents of air that humans need for survival?

Nitrogen and Oxygen

Which type of sources are chimneys used for dispersing combustion products considered as?

Point Sources Signup and view all the answers

What is the term for pollutants that are laterally so extensive that a specific point of emission cannot be readily identified?

Non-point Pollutants Signup and view all the answers

Which gas plays a major role in tropospheric ozone formation, has a reddish-brown color, and can irritate the lungs?

Nitrogen Dioxide (NO2) Signup and view all the answers

What is the major health effect associated with exposure to high concentrations of ozone?

Eye irritation Signup and view all the answers

Which scientist discovered Chlorofluorocarbons (CFCs) in 1930, initially thought to be inert, but later found to cause ozone depletion?

Thomas Midgley Jnr. Signup and view all the answers

What is the consequence of the presence of greenhouse gases like CO2, CH4, NxOx, CFCs, and O3 in large quantities in the atmosphere?

Global warming Signup and view all the answers

At what concentration do many plants, particularly coniferous plants, get damaged by Sulfur Dioxide (SO2)?

$0.3$ - $0.5$ ppm Signup and view all the answers

Study Notes

Atmospheric Air

Air is essential for human survival, with an average daily need of 14 kg, compared to 2 kg of water and 1 kg of food.
Air is a mixture of 13 different gases, primarily consisting of Nitrogen (78%), Oxygen (21%), Argon and other gases (0.9%), and Carbon Dioxide (0.03%).

Air Pollutants

The major atmospheric pollutants include Carbon monoxide (CO), Hydrocarbons (HC), Oxides of nitrogen (NOx), Oxides of sulphur (SOx), and Particulates (solids and liquids).
Other pollutants include Carbon Dioxide (CO2), Chlorofluorocarbons (CFCs), and more.

Sources of Pollution

Point Sources: include chimneys, processing minerals, drilling, crushing, screening, conveyors, and transhipment points.
Non-point Sources: include blasting, haulage roads, and other extensive sources that cannot be readily identified.

Industrial Pollutants

Gaseous pollutants: include Carbon Dioxide (CO2), Carbon Monoxide (CO), Sulphur Dioxide (SO2), Nitrogen Oxides (NOx), and Ozone (O3).
Particulates: include smoke, soot, and other suspended particles.

Carbon Dioxide (CO2)

Not typically considered a pollutant, but causes the "Greenhouse effect" when present in large quantities.
Estimated to have increased by 26% between 1860 and 1986, and expected to double by 2040.

Carbon Monoxide (CO)

Colourless, odourless, and tasteless gas with adverse health effects, including impaired oxygen delivery to organs and tissues.
Most detrimental to people with cardiovascular diseases.

Sulphur Dioxide (SO2)

Highly destructive pollutant with adverse effects on human health, including respiratory illnesses, cardiovascular diseases, and death.
Damages plants at concentrations above 0.3-0.5 ppm, particularly coniferous plants.

Nitrogen Oxides (NOx)

Nitrogen oxide (NO) is a reactive gas that contributes to tropospheric ozone formation.
Nitrogen Dioxide (NO2) irritates lungs, causes bronchitis and pneumonia, and lowers resistance to respiratory infections.

Ozone (O3)

A colourless gas that affects healthy adults and children, as well as people with impaired respiratory systems.
Reduces lung function, causes coughing, sneezing, chest pain, and pulmonary congestion.

Chlorofluorocarbons (CFCs)

Discovered in 1930, initially considered inert, but now known to react with Ozone (O3) and cause ozone layer depletion.
Depletion of the ozone layer allows hazardous ultraviolet radiations into the troposphere, causing skin cancers.

Greenhouse Gases

Gases like CO2, CH4, NxOx, CFCs, and O3, which contribute to the "Greenhouse effect" and global warming when present in large quantities.