What Does Photochemical Smog Mean


What Does Photochemical Smog Mean?

What is photochemical 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. Primary pollutants.

What is photochemical smog and what are its effects?

Photochemical smog is formed when pollutants like hydrocarbons and nitric oxide interact with sunlight to form chemicals like NO2 Peroxyacyl nitrate (PAN) ozone acrolein and formaldehyde. … Photochemical smog leads to cracking of rubber and extensive damage to plant life.

What is photochemical smog caused by?

Photochemical smog is produced when sunlight reacts with nitrogen oxides and at least one volatile organic compound (VOC) in the atmosphere. Nitrogen oxides come from car exhaust coal power plants and factory emissions.

What does the term photochemical mean?

Definition of photochemical

1 : of relating to or resulting from the chemical action of radiant energy and especially light photochemical smog. 2 : of or relating to photochemistry photochemical studies.

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.

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


See also how did imperialist european powers claim control over most of africa by the end of the 1800s

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 are the harmful effects of photochemical smog How does it formed?

Photochemical smog has many adverse effects. When combined with hydrocarbons the chemicals contained within it form molecules that cause eye irritation. Radicals in the air interfere with the nitrogen cycle by preventing the destruction of ground level ozone.

What 2 pollutants are main ingredients in photochemical smog?

The two major primary pollutants nitrogen oxides and VOCs combine to change in sunlight in a series of chemical reactions outlined below to create what are known as secondary pollutants.

What color is photochemical smog?


Photochemical smog is a brownish-gray haze caused by the action of solar ultraviolet radiation on atmosphere polluted with hydrocarbons and oxides of nitrogen.

What is photochemical smog Class 11?

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.

What is the best definition of a photochemical?

noun. 1. The branch of chemistry having to do with the effect of light or other radiant energy in producing chemical action as in photosynthesis or photography.

What is the photochemical phase?

The photochemical phase of photosynthesis is also known as light reaction. It is responsible for the formation of high-energy chemical intermediates ATP and NADPH and it includes light absorption water splitting and release of oxygen.

Is photochemical smog always contains ozone?

The photochemical smog always contains the Ozone gas or O3 as a pollutant. So the correct answer is “Ozone”. Note: – The presence of ozone is explained by a concept known as the photostationary state.

How is industrial smog and photochemical smog?

It is produced when nitrogen oxides and volatile organic compounds in automobile and fossil-fueled power-plant emissions combine with oxygen in the air in direct sunlight. Whereas industrial smog casts a gray pallor over the areas it affects the nitrogen dioxide in photochemical smog creates a dingy brownish haze.

What is the main difference between photochemical smog and sulfurous or London smog?

Classical Smog vs Photochemical Smog
London smog or Classical smog Los Angeles smog or Photochemical smog
This type of smog is first observed in 1952 in London. This type of smog was first observed in 1943 in Los Angeles.
It involves smoke and fog (smog) The word smog is misnomer here as it does not involve any smoke or fog.

See also how do heavy sediment deposits affect waterways

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).

Where would a person be most exposed to photochemical smog?

It is created by a chemical reaction that takes place in exhaust and in the presence of sunlight. The gas is acrid-smelling and whitish. Warm dry cities surrounded by mountains such as Los Angeles Phoenix and Denver are especially prone to photochemical smog (Figure below).

How is photochemical smog control?

Walk or bike to places that are short distances away instead of driving. Combine trips and fill up with gasoline after dark. Reduce electricity usage. Burning coal is the primary source of electrical production so avoid excessively using electricity.

How is ozone formed in photochemical smog?

VOCs + NOx = Ozone. These volatile organic compounds react to form ozone only in the presence of sunlight. … This blue light is producing the UV light that is required to create ozone. And this ozone again reacts with volatile organic compounds to produce photochemical smog.

What is photochemical smog Slideshare?

Photochemical Smog is an air pollution formed when photons of sunlight hit molecules of different kinds of pollutants in the atmosphere. AIR POLLUTANT Primary Air Pollutant NOx VOCs Secondary Air Pollutant Ozone(O3) PAN. Process Involving Formation Of Photochemical Smog.

What is 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.

What is photochemical smog Wikipedia?

Photochemical smog often referred to as “summer smog” is the chemical reaction of sunlight nitrogen oxides and volatile organic compounds in the atmosphere which leaves airborne particles and ground-level ozone. Photochemical smog depends on primary pollutants as well as the formation of secondary pollutants.

What do you mean by photochemical reaction give example?

A Photochemical reaction is a reaction which takes place when a chemical process absorbs light energy as its energy source. The example is photosynthesis. … The photons from the light energy split water and enable ATP production that drives the entire process.

What is a photochemical reaction What is the major component of most photochemical smog?

Ground-level ozone constitutes one of the major components of photochemical smog so called because of the photochemical reaction of air pollutants such as nitrogen oxides (NOx) and volatile organic compounds (VOCs) with ultraviolet light (sunlight) thus the O3 levels vary strongly with season and the highest levels …

What are photochemical properties?

Photochemistry is the branch of chemistry concerned with the chemical effects of light. Generally this term is used to describe a chemical reaction caused by absorption of ultraviolet (wavelength from 100 to 400 nm) visible light (400–750 nm) or infrared radiation (750–2500 nm).

See also what is the final thermal energy of the gas a?

What is photochemical phase and biosynthetic?

Photosynthesis comprises of two phases first phase is the photochemical phase or light dependent process (light reaction) and second phase is the biosynthetic phase or dark reaction of photosynthesis. The whole process of photosynthesis takes place within the chloroplast.

What is the difference between photochemical phase and biosynthetic phase?

The first phase is the photochemical phase or light-dependent process. This phase is commonly known as the light reaction. The second phase is the biosynthetic phase of the dark reaction of photosynthesis. This phase is the light-independent process.

What is Blackman’s reaction?

The Blackman reaction is the name given to the rate-determining process. when photosynthesis is saturated with both light and carbon dioxide. We. define its rate as the number of cubic millimeters of oxygen produced per. hour by one cubic millimeter of cells under saturating conditions.

Does nitrous oxide cause ozone depletion?

“Right now nitrous oxide is the most important ozone-depleting gas that is emitted ” says A. R. Ravishankara of the US National Oceanic and Atmospheric Administration lead author of the new research.

Is methane present in photochemical smog?

Photochemical Smog and Climate Change. While NO2 is major component of photochemical smog and the focus of this Case Study several other components of smog also deserve mention because of their role in climate change. These gases include Methane (CH4) Nitrous Oxide (N2O) and Ozone (O3).

Which of the following are likely to be present in a photochemical smog?

Nitrogen oxides such as nitrogen dioxide. Peroxyacyl nitrates. Tropospheric ozone. Volatile organic compounds.

Is photochemical oxidants present in photochemical smog?

Photochemical oxidants are found in ‘photochemical smog’ which is a complex mixture of primary and secondary air pollutants. The photochemical oxidants are secondary air pollutants formed by the action of sunlight on nitrogen oxides and reactive hydrocarbons their precursors.

What is photochemical smog and classical smog?

1. classical smog – This is the typical form of smog found in areas which have a humid climate. It is a mixture of smoke fog and sulphur dioxide. … Photochemical smog – This type of smog is prevalent in dry and sunny areas of the world.

What is industrial photochemical smog?

Both industrial smog and photochemical smog are forms of air pollution. … Industrial smog typically exists in urban areas where factories burn fossil fuels such as coal which creates smoke and sulfur dioxide that mix with fog droplets to create a thick blanket of haze close to the ground.

Photochemical Smog (Animation)

The science of smog – Kim Preshoff

What does photochemical smog mean?

Lecture 3.2 Photochemical Smog

Leave a Comment