Secondary pollutants are pollutants which form in the atmosphere. These pollutants are not emitted directly from a source (like vehicles or power plants). Instead, they form as a result of the pollutants emitted from these sources reacting with molecules in the atmosphere to form a new pollutant.Sep 27, 2021
Examples of a secondary pollutant include ozone, which is formed when hydrocarbons (HC) and nitrogen oxides (NOx) combine in the presence of sunlight; NO2, which is formed as NO combines with oxygen in the air; and acid rain, which is formed when sulfur dioxide or nitrogen oxides react with water.
Primary pollutants include ammonia, sulfur dioxide, nitrogen dioxide and carbon monoxide. Secondary pollutants include ground-level ozone, acid rain and nutrient enrichment compounds.
Secondary pollutants are not emitted directly. They are formed from the combination of primary pollutants with some other compound. Examples of secondary pollutants are Ozone, Formaldehyde, PAN (peroxy acetyl nitrate) and Smog etc.
Smog is not a secondary pollutant. Smog is air pollution that reduces visibility.
The major primary pollutants are Oxides of Sulphur, Oxides of Nitrogen, Oxides of Carbon, Particulate Matter, Methane, Ammonia, Chlorofluorocarbons, Toxic metals etc. … The secondary pollutants are not emitted directly.
Peroxyacetyl nitrate (PAN) and ozone are the two important secondary photochemical air pollutants found in the urban at- mosphere (1-3). Of the two, PAN is the more useful indicator of photochemical reactions in polluted air as, unlike ozone, it appears to have no large natural source (2-7).
Secondary pollutants may be either gaseous, or particulate aerosols. … Aerosol pollutants may be formed within the atmosphere as a result of gas-phase reactions followed by condensation of the products, or by reactions taking place in the existing atmospheric aerosol phase.
Ground-level ozone is a colorless and highly irritating gas that forms just above the earth’s surface. It is called a “secondary” pollutant because it is produced when two primary pollutants react in sunlight and stagnant air. These two primary pollutants are nitrogen oxides (NOx) and volatile organic compounds (VOCs).
Carbon Monoxide (CO)
Carbon monoxide is released from volcanoes and forest fires as well. Secondary pollutants like ozone and carbon dioxide (CO2), a greenhouse gas, come from carbon monoxide.
Hint: To answer this question you should know that a primary pollutant is an air pollutant emitted from a source directly into the atmosphere and a secondary pollutant is an air pollutant formed in the atmosphere as a result of interactions between the primary pollutants and other atmospheric components.
Primary Pollutants | Secondary Pollutants |
---|---|
Carbon monoxide (CO) Oxides of nitrogen (NOx, NO) Sulfur oxides (SOx) Volatile organic compounds (VOCs) highly Particulate matter (dust, ash, salt particles) | Ozone PAN Smog Formaldehyde Sulphuric Acid |
Different types of secondary pollutants include: Ozone (O3) Sulfuric acid and nitric acid (component of acid rain) Particulate matter.
3. Which of the following is called the secondary air pollutant? Sol: (b) Ozone.
Like nitrogen dioxide, sulfur dioxide can create secondary pollutants once released into the air. Secondary pollutants formed with sulfur dioxide include sulfate aerosols, particulate matter, and acid rain.
Ozone, unlike the other criteria pollutants, is not emitted directly into the air by any one source. Ground-level ozone is a secondary pollutant. It is formed through chemical reactions of other molecules already in the air, specifically nitrogen oxides (NOx) and volatile organic compounds (VOCs).
Though nitrogen dioxide can be a primary pollutant, it’s mostly a concern as a secondary pollutant. As a primary pollutant, NO2 is emitted in limited amounts through vehicles into the air. Nitrogen dioxide is also a secondary pollutant because it can be formed through oxidisation.
The top 10, in alphabetical order, are: artisanal gold mining; contaminated surface water; contaminated groundwater; indoor air pollution; metals smelting and processing; industrial mining; radioactive waste and uranium mining; untreated sewage; urban air quality; and used lead–acid battery recycling.
Primary pollutants enter the air directly. They include carbon oxides, nitrogen oxides, sulfur oxides, particulates, volatile organic compounds (VOCs), and heavy metals. Secondary pollutants form from primary pollutants.
Therefore, the correct answer is option C (PAN).
PANs are a secondary pollutant since they form in the atmosphere after the emission of primary pollutants. Sources of the pollutants required to create PANs include motor vehicles, tobacco smoke, and the burning of fossil fuels.
Secondary pollutants are more harmful than primary pollutants because the harmful gases produced by primary pollutants like carbon monoxide can result in air pollution in the atmosphere. … Secondary pollutants can result in Acid deposition.
It is produced in the atmosphere when oxidized volatile organic compounds combine with nitrogen oxide. It is a component of photochemical smog. PANs create health problems such as reduced respiratory function and eye irritation, and may also be linked to emphysema, impaired breathing and other lung problems.
Primary pollutants, the beginning of the chain
It is a precursor of CO2 and ozone. Sulfur dioxide (SO2), which reaches the atmosphere mainly as a consequence of human activities such as the burning of coal or oil. Natural sources such as volcanoes also contribute a remarkable percentage.
Secondary air pollutants are photochemically produced from primary pollutants and are thus called photochemical oxidants. Ozone, peroxyacyl nitrates, aldehydes and phenols are produced due to photochemical reactions between nitrogen oxides and unsaturated hydrocarbons.
Nitrogen oxides come from car exhaust, coal power plants, and factory emissions. VOCs are released from gasoline, paints, and many cleaning solvents. When sunlight hits these chemicals, they form airborne particles and ground-level ozone—or smog.
Volatile Organic Compounds (VOCs) are a large group of chemicals that are found in many products we use to build and maintain our homes. Once these chemicals are in our homes, they are released or “off-gas” into the indoor air we breathe.
Related Searches
primary and secondary pollutants examples
secondary pollutants examples
primary pollutants examples
is pan a secondary pollutant
primary air pollutants
primary pollutants wikipedia
primary and secondary air pollutants
what is smog is it a primary or secondary pollutant