Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities. It tends to occur more often in summer, because that is when we have the most sunlight.

How photochemical is formed?

Photochemical form is formed by a complex series of chemical reactions involving sunlight, oxides of nitrogen, and volatile organic compounds that are present in the atmosphere as a result of air pollution. These reactions often result in the formation of ground level ozone and certain airborne particles.

How is photochemical smog formed quizlet?

Photochemical smog is formed when nitrogen oxides (NOx) and volatile organic hydrocarbons react when activated by sunlight. … 3) When exposed to UV radiation from the sun, some NO2 reacts with hydrocarbons to form photochemical oxidants such as ozone, nitric acid, aldehydes and other pollutants.

What is photochemical smog how is it formed and how does it effects?

Photochemical smog refers to a type of smog which is formed when the ultraviolet light from the sun reacts with nitrogen oxides present in the atmosphere. This smog can cause a lot of adverse effects on humans and other living organisms.

Which gas is formed in photochemical smog?

Among the pollutants involved in photochemical smogs are ozone, nitrogen dioxide and peroxyacyl nitrate (PAN). The nitrogen dioxide, and other oxides of nitrogen, are primary pollutants produced by dissociation in combustion reactions, and both ‘prompt’ and ‘thermal’ NOx can be involved in the reactions.

What is photochemical smog Class 10?

Hint: Photochemical smog, which is often referred to as the summer smog, is the chemical reaction of sunlight, nitrogen oxides and volatile organic compounds that are present in the atmosphere, which leaves airborne particles harmful for the health and ground-level ozone.

What is the composition of photochemical smog *?

The major undesirable components of photochemical smog are nitrogen dioxide (NO2), ozone (O3), PAN (peroxyacetylnitrate), and chemical compounds that contain the –CHO group (aldehydes).

What are the effects of photochemical smog?

Ozone and nitric oxide (NO) can irritate the nose and throat and their high concentration causes a headache, chest pain, dryness of the throat, cough and difficulty in breathing. Photochemical smog leads to cracking of rubber and extensive damage to plant life.

What are the effects of photochemical smog How can photochemical smog be controlled?

CONTROL MEASURES: Photochemical smog is obtained from the burning of fossil fuels and automobile fuels that emit NO2 and hydrocarbons, which in turn form ozone, PAN, and other chemicals. To prevent the release of NO2 and hydrocarbons into the atmosphere, the use of catalytic converters in automobiles is recommended.

What is a photochemical smog quizlet?

– Photochemical smog is a yellow-brown haze due to nitrogen dioxide. – The presence of this gas and other pollutants can cause health problems. Formation of nitrogen oxides. – Nitrogen oxides are formed in high temperature engines and furnaces.

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How is photochemical smog formed what secondary pollutant is a major component?

Smog forms when sunlight, nitrogen oxides, and volatile organic compounds are present. The secondary pollutant ozone is a major component of photochemical smog. … Acidic desposition, which is comprised of hydrogen, sulfate, and nitrate ions, forms from both sulfur dioxide and nitrogen oxides.

Where does photochemical smog occur?

Photochemical smog, which is also known as “Los Angeles smog,” occurs most prominently in urban areas that have large numbers of automobiles. It requires neither smoke nor fog. This type of smog has its origin in the nitrogen oxides and hydrocarbon vapours emitted by automobiles…

How does photochemical smog and acid rain form?

Photochemical smog forms from a complex process, however the source of it is quite apparent. … The nitric acid may precipitate to the Earth resulting in acid rain, or remain in the smog. Due to the direct production of it by vehicles, the smog forms over cities where many people may encounter its adverse health effects.

What is photochemical smog list the factors that favor the formation of photochemical smog?

Photochemical smog development factors 1-Nitrogen source and released organic combinations, combining high density of this material with industrializing and transportation are important factors forming photochemical smog. These factors cause some pollution to form in atmosphere by combustion fossil fuel.

How are solid particulates formed?

1.2 How are particles formed? Coarse particles are produced by the mechanical break-up of larger solid particles. The coarse fraction can include dust from roads, agricultural processes, uncovered soil or mining operations, as well as non-combustible materials released when burning fossil fuels.

What is the main oxidant in photochemical smog?

The photochemical oxidants are secondary air pollutants formed by the action of sunlight on nitrogen oxides and reactive hydrocarbons, their precursors. The most important phytotoxic components produced by these atmospheric photochemical reactions are ozone and peroxyacetyl nitrate.

What is the difference between smog and photochemical smog?

Sulfurous smog, also known as London smog, develops due to high concentration of sulfur oxides in the air. … Photochemical smog is produced when sunlight reacts with oxides of nitrogen and at least one volatile organic compound (VOC) in the atmosphere.

Which air pollutant causes corrosion of building?

The most notorious pollutant responsible for metallic corrosion is sulphur dioxide, it has been reported that corrosion of hard metals such as steel begins at annual mean concentrations of 0.02 ppm.

Is formaldehyde a component of photochemical smog?

The common components of photochemical smog are ozone, nitric oxide, acrolein, formaldehyde and peroxyacetyl nitrate (PAN).

Is photochemical smog a secondary pollutant?

Secondary pollutants are pollutants which form in the atmosphere. These pollutants are not emitted directly from a source (like vehicles or power plants). … Photochemical smog is made up of various secondary pollutants like ozone, peroxyacyl nitrates (PANs), and nitric acid (seen in Figure 2).

Which is not true about photochemical smog?

The high concentration of photochemical smog in the atmosphere causes irritation in eyes, headache, throat dryness and chest pain along with multiple respiratory ailments. Thus, the statement ‘photochemical smog causes irritation in eyes’ is true. Thus, option (A) is not correct.

What is photo chemical smog?

Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities. It tends to occur more often in summer, because that is when we have the most sunlight.

What is smog quizlet?

-Smog: a poisonous mixture of smoke, aire, and other pollutants. -need: emissions, warmth/sunlight, and no air movement.

Which pollutant is the major contributor to photochemical smog?

Option 2 is the correct answer: Ozone is the major contributor to photochemical smog.

What causes smog formation of acid rain?

Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.