(c) Both A and R are not correct. E14.4.1) and Los Angeles, where cars are virtually the only means of transportation. Difference Between Industrial Smog & Photochemical Smog. It was first reported over Los Angeles in $1940s$. The word “smog” was originally coined as a mixture of “smoke” and “fog” and was historically used to describe air pollution produced from the burning of coal, which released smoke and sulfur dioxide. X is Photochemical smog depends on primary pollutants as … Photochemical smog, which occurs most prominently in urban areas that Learn more. It contains 3 modules: SCREEN3, PUFF, and RVD (Relief Valve Discharge). Motor vehicles, powered by fossil fuels, produce chemical-laced fumes. 2 Photochemical Smog Although composed of 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.03% carbon diox-ide, and less than 4% water vapor, the Earth’s atmosphere also contains minute amounts of nearly forty other gases such as ozone, helium, hydrogen, nitrogen oxides, and sul-fur dioxides, [46]. The major undesirable components of photochemical smog are nitrogen dioxide (NO2), ozone (O3), PAN (peroxyacetylnitrate), and chemical compounds that contain the –CHO group (aldehydes). That means if the fuel system is unsealed or open to the atmosphere, it can pollute 24 hours a ⦠The industrial revolution has been the central cause for the increase in pollutants in the atmosphere over the last three centuries. d) automobile use . Photochemical smog (or just smog for short) is a term used to describe air pollution that is a result of the interaction of sunlight with certain chemicals in the atmosphere. Volatile organic compounds come not only from hydrocarbons that are not burned in internal combustion engines, but from various sources, such as evaporation of solvents and fuels, among others. The smog contains toxic pollutants like PM2.5, PM10, carbon monoxide (CO), methane (CH4), carbon dioxide (CO2) and nitrogen oxide (NOx). The exhaust gases from a cement kiln contains are nitroge n oxides (NOx), carbo n . The formation of photochemical smog … Historically, the term smog referred to a mixture of smoke and fog, hence the name 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. When it is exposed to ultraviolet radiation, the NO 2 molecule is known to undergo a complex series of hydrocarbon reactions to produce the photochemical smog components. In the classical sense, smog equals smoke plus fog, but for the people who live in sun-drenched basins, such as Los Angeles, the equation is a little more complicated. These combine with the water in fog to produce acidic precipitation -- sulfur dioxide dissolves in water to form sulfuric acid -- and thick, tar-laden droplets. Distinct from the historic 1952 London fog mainly caused by coal combustion and the Los Angeles smog mainly caused by photochemical oxidation of vehicular emissions (5, 41), haze pollution in China is the consequence of diverse, high primary emissions and efficient secondary production (8, ⦠Smog And Acid Rain Smog. Industrial smog contains two primary components: sulfur dioxide and particulate matter. This layer extends about 11 miles above sea level at the equator and about 5 miles above the poles. Combustion of a fossil fuel which contains sulfur impurities: ... and they also react in the atmosphere with other pollutants to make photochemical smog. The main components of photochemical smog are nitrogen oxides, Volatile Organic Compounds (VOCs), … Energy, Ch. 4. 1.1 What is ozone? Components of Photochemical Smog Photochemical smog requires neither smoke nor fog. The burning of fossil fuels is the main reason for photochemical smog. [Return to Table of Contents] Ozone (O 3) is the primary ingredient of photochemical smog, the type of air pollution that is associated with sunlight-driven chemical reactions.Ozone is associated in particular with the type of air pollution events that occur in Los Angeles and Mexico City, often associated with automobile emissions. 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. Due to their low boiling points, VOCs can be emitted to the It is the chemical reaction of sunlight, nitrogen oxides and volatile organic compounds in the atmosphere, which leaves airborne particles and ground-level ozone. It contains anthropogenic air pollutants, mainly ozone, nitric acid, and organic compounds, which ⦠Photochemical Smog and Ozone Depletion. It 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 appears in the form of a brownish haze that remains stationary when the weather is stable, since the air does not circulate and the pollution does not dissipate . Smog is a compound word of smoke and fog which means fog that contains air pollutants. The absorption of solar radiation by the nitrogen dioxide results in the formation of ozone (O3). When fossil fuels such as petrol and diesel burn, they leave hydrocarbons, that forms ozone, PAN, other chemicals in the atmosphere. (a) Both A and R are true and R is the correct explanation of A. Industrial smog usually forms in cool, humid environments, and it contains large numbers of tiny aerosol particles that make it appear gray. The dataset contains the results of a study examining the impact of vitamin D deficiency on the cardiopulmonary response of mice to photochemical smog. It forms a yellowish brown haze especially during winter and hampers visibility. (b) Both A and R are correct and R is not the correct explanation of A. Below are the main causes of Smog… It mainly consists of nitrogen dioxide (NO 2), ozone (O 3), peroxyacetyl nitrate (PAN), and organic compounds containing the aldehyde group. Photochemical smog is formed at high temperature over cities and towns due to still air, emission of nitrogen oxides etc. It appears as a grayish haze in the skies above heavily industrialized cities. It contains smoke, fog and sulphur dioxide. Photochemical smog is a grey or yellowish brown opaque smog having an oxidising environment with a little smoke. It contains anthropogenic air pollutants, mainly ozone, nitric acid, and organic compounds, which are trapped near the ground by temperature inversion. Assertion(A) :-Photochemical smog is oxidising in nature. photochemical smog. Chlorofluorocarbons are of concern in the atmosphere because they destroy stratospheric ozone. ... (photochemical smog), it heats us in the troposphere (greenhouse gas) and protects us in the stratosphere (ozone layer). Photochemical smog was first described in the 1950s. It also is a cause of many respiratory disorders and allergies as it contains polluting gases. This magnetic tape contains the FORTRAN source code, sample input data, and sample output data for the Photochemical Box Model (PBM). Reason (R): Photochemical smog contains N0 2 and 0 3, which are formed during the sequence of reactions. Photochemical smog, which is also known as “Los Angeles smog,” occurs most prominently in urban areas that have large numbers of automobiles. Primary and secondary pollutants. As the reaction take place in the presence of light to form the smog, it is called photochemical smog. Even after smog was … Assertion(A) :-Photochemical smog is oxidising in nature. e) burning of coal in power plants 23. Although photochemical smog is often invisible, it can be extremely harmful, leading to irritations of the respiratory tract and eyes. Smog is a byproduct of modern industrialization. The word ‘smog’ is derived from the two words-smoke and fog. Ozone reacts with many different hydrocarbons to produce a brownish-yellow gaseous cloud which may contain numerous chemical compounds, the combination of which, we call photochemical smog. It is formed when the air contains NO 2 and hydrocarbons and the mixture is exposed to sunlight. Classical smog is also called London-type smog which occurs in the regions where emission of the sulphur containing compounds is high (e.g., due to burning of coal) and air contains high liquid water contents (e.g., fogs). It is formed when the air contains NO 2 and hydrocarbons and the mixture is exposed to sunlight. Example from the Hansard archive. Photochemical smog is a unique type of air pollution. Photochemical smog is mainly composed of ozone (O 3), peroxyacetyl nitrate (PAN) and NO x. (b) Both A and R are true but R is not the correct explanation of A. It was first described over 5 decades ago as a mixture of smoke and fog, hence the name "smog"—but today it has a more specific definition and composition. Note that industrial smog—sometimes called sulfurous or black smog—is distinct from photochemical smog, which typically develops in warmer conditions in the summer. As long as the e:m ratio increases, O 3 and PAN concentrations at LAC also increase. This type of smog has its origin in the nitrogen oxides and hydrocarbon vapours emitted by automobiles…. Photochemical smog is a condition that develops when primary. General Definition and Classifications. Reason (R): Photochemical smog contains N0 2 and 0 3, which are formed during the sequence of reactions. Acid rain does significant damage to natural ecosystems and forests, particularly in the northeastern United States. Contains Parliamentary information licensed under the Open Parliament Licence v3.0. for the mcq Photochemical smog consists of excessive amount of X in addition to aldehydes, ketones, PAN etc. Nitrogen dioxide, NO 2, is produced in the exhaust from motor vehicles, and reacts with hydrocarbons in the air to produce photochemical smog. This is a mixture of gases and since it is formed by photochemical reactions, it is called the photochemical smog. When fossil fuels such as petrol and diesel burn, they leave hydrocarbons, that forms ozone, PAN, other chemicals in the atmosphere. (b) Both A and R are true but R is not the correct explanation of A. Furthermore, photochemical smog contains PAN, acrolein, and formaldehyde. Reason(R) :-Photochemical smog contains NO2 and O3 asked Jun 7, 2018 in Chemistry by rubby ( 51.7k points) Smog is a specific type of air pollution.It is a combination of harmful pollutants (often appearing relatively low to the ground as a yellow-brown haze) that are introduced into the atmosphere by both natural and human induced processes. The burning of fossil fuels is the main reason for photochemical smog. Industrial smog consists of a mixture of sulphur dioxide, suspended droplets of sulphuric acid, and a variety of suspended solid particles. smog definition: 1. a mixture of smoke, gases, and chemicals, especially in cities, that makes the atmosphereâ¦. An important indicator for these photochemical processes is the e:m ratio measured at LAC. Volatile organic compounds (VOC) means any compound of carbon, excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates and ammonium carbonate, which participates in atmospheric photochemical reactions, except those designated by EPA as having negligible photochemical reactivity 2. Smog is air pollution that reduces visibility.The term "smog" was first used in the early 1900s to describe a mix of smoke and fog.The smoke usually came from burning coal.Smog was common in industrial areas, and remains a familiar sight in cities today. Other pathways for ozone formation in the troposphere are complex reactions involving nitrogen oxides, hydrocarbons and oxygen. Smog contains soot particulates like smoke, sulphur dioxide, nitrogen dioxide and other components. Photochemical smog is a unique type of air pollution which is caused by reactions between sunlight and pollutants like hydrocarbons and nitrogen dioxide. Smog covered the city and its surrounding area from November 23 to 26, filling the city's air with damaging levels of several toxic pollutants. Photochemical smog results in reduced visibility, irritation of the eyes, and respiratory diseases in humans. a) atmospheric inversion. Smog is the visible gaseous and particular matter concentrating near the earth's surface particularly in the cities due to SO 2, CO 2, factory and traffic emission and meteorological conditions.When different gases like SO 2, NO 2, N 2 O, NO 2, unburnt hydrocarbons etc.