Guys, does anyone know the answer?
get which of the following components in the air is difficult to detect by a simple test from screen.
Air Pollution Questions
Air Pollution Questions and Answers - Practice questions, MCQs, PYQs, NCERT Questions, Question Bank, Class 11 and Class 12 Questions, NCERT Exemplar Questions, and PDF Questions with answers, solutions, explanations, NCERT reference, and difficulty level in air pollution chemistry.
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Air Pollution Questions
Air pollution is the poisoning of air caused by the presence of compounds in the atmosphere that are hazardous to human and other living beings’ health, as well as to the environment and materials.
Gases (like ammonia, carbon monoxide, sulphur dioxide, nitrous oxides, methane, carbon dioxide, and chlorofluorocarbons), particles (including organic and inorganic), and living molecules are all examples of air pollution.
Many pollution-related disorders, including respiratory infections, heart disease, COPD, stroke, and lung cancer, are all linked to air pollution.Definition: Air pollution is described as introducing pollutants, organic molecules, or other unsafe materials into Earth’s atmosphere. This can take the form of excess gases like carbon dioxide and other vapours that aren’t adequately eliminated by natural cycles like the carbon or nitrogen cycles.
Air Pollution Chemistry Questions with SolutionsQ1: What are the natural causes of air pollution?Answer:
Natural sources of air pollution include forest fires and volcanoes, which pollute the air with smoke and dust.Q2: How do automobiles pollute the air?Answer:
Internal combustion engines, which run on gasoline or diesel, are common in automobiles. When gasoline or diesel is burned, various harmful gases are released, including carbon dioxide, carbon monoxide, sulphur dioxide, nitrogen dioxide, and others. Furthermore, automotive engines emit microscopic particles. As a consequence, automobiles pollute the atmosphere.Q3: Write a short note on the ozone layer.Answer:
The ozone layer serves as a protective layer in the atmosphere. It has the highest concentration of ozone of any layer of the atmosphere. However, when compared to other gases, ozone makes up a small percentage of the air in the ozone layer. This layer blocks the sun’s harmful UV rays from entering our atmosphere. UV rays cause skin cancer in people and animals and are also hazardous to plants. Any disruption to the ozone layer can have severe consequences for living things.Q4: What is the greenhouse effect? What is the impact of the greenhouse effect?Answer:
Carbon dioxide and methane are examples of greenhouse gases that trap solar energy and thus raise the atmospheric temperature. This is known as the greenhouse effect. Greenhouse effect tends to result in global warming.Q5: Supersonic jets cause pollution by thinning of
(a) Sulphur dioxide layer
(b) Ozone layer
(c) Carbon dioxide layer
(d) None of theseAnswer: (b) Ozone layerQ6: Clouds are present in-
(a) stratosphere (b) troposphere (c) mesosphere (d) thermosphereAnswer: (b) troposphereQ7: Global warming is caused due to____ concentration of CO2 in the air
(a) Decreased (b) Increased (c) Both (a) & (b) (d) None of theseAnswer: (b) IncreasedQ8: Which of the following gases can deplete the upper atmosphere’s ozone layer?
(a) Ammonia (b) Carbon monoxide (c) Methane (d) Sulphur dioxideAnswer: (c) MethaneQ9: Air pollution causing photochemical oxidants production includes
(a) Carbon monoxide, sulphur dioxide
(b) Nitrous oxide, nitric acid fumes, nitric oxide
(c) Oxygen, chlorine, fuming nitric acid
(d) Ozone, peroxyacetyl nitrate, aldehydesAnswer: (d) Ozone, peroxyacetyl nitrate, aldehydesQ10: CFCs are not recommended to be used in refrigerators because they
(a) Increase temperature
(b) Affect environment
(c) Deplete ozone
(d) Affect human bodyAnswer: (c) Deplete ozoneQ11: Is there an air pollution level that is safe for our health?Answer:
While everyone’s health is affected differently by air pollution, there is no evidence of a perfectly acceptable level of air pollution in large cities or countries, especially when it comes to particle matter. However, to assist countries in achieving cleaner air for health, the WHO has established normative guideline levels for all primary air contaminants, above which detrimental health effects are probable.
This is not to suggest that there are no health effects below those limits; rather, they are health-based targets that can be used to track the burden of disease caused by air pollution, inform national targets and standards, and track the effectiveness of air quality management efforts aimed at improving health.
National air quality standards have been set in several countries. National standards might vary by nation and higher or lower than the relevant WHO guideline value. Determining which specific at-risk populations should be safeguarded by the guidelines and what level of risk is acceptable is a policy issue. On the other hand, many countries are working to satisfy the WHO air quality criteria and intermediate targets.Q12: Briefly describe the types of air pollution.Answer:
There are two types of air pollution.1. Man-made (Artificial) Sources
Components of Air
We all are aware of the vital role that air plays in our survival. But what is air? Air which is also commonly known as the atmosphere is a mixture of various gases. Let’s get a thorough look at the composition of air due to which life is possible on Earth.
Components of Air
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What are the Components of Air?
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We all are aware of the vital role that air plays in our survival. But what is air? Air which is also commonly known as the atmosphere is a mixture of various gases. The first thing that pops up in our mind when we think about air is Oxygen, which is essential for the existence of life on Earth. But oxygen is not the only element that air is composed of. Other gasses also play an important role in sustaining life. Let’s get a thorough look at the composition of air due to which life is possible on Earth.
Composition of Air
Air is made up of 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and other gases in meagre amounts. Water vapour is also a constituent of air in varying amounts, along with dust particles. The molar mass of dry air or air with no/low quantity of water vapour in it is 28.97g/mol. We can find out the average molar mass of a mixture of gases by using a simple formula in which we take the summation of the molar mass of each gaseous component multiplied by its mole fraction.
Fig: Composition of air
M mixture = x1M1+.....+xnMn, where,
xi= mole fraction of each gas
Mi= the molar mass of each gas
Mole fraction or xi= Number of Moles of that ComponentTotal Number of Moles in the Mixture
Mole fraction or xi =
Number of moles of that Component
Total Number of Moles in Mixture
Number of moles of that ComponentTotal Number of Moles in Mixture
Main Components of Air
The main components of air are given as,
Oxygen is the most important chemical elements of which air is composed. It has the symbol O and has an atomic number of 8. Oxygen is a highly reactive gas that readily forms bonds known as oxides with other elements. It is also highly combustible (quick to catch fire). In terms of mass, after hydrogen and helium, oxygen is the most copious element in the universe. If we consider the standard temperature, which is 273.15K, and the standard pressure, being 1atm, then two atoms of oxygen combine to form one molecule of oxygen known as dioxygen (O2). Dioxygen is used for cellular respiration or breathing.
Oxygen is needed not only for respiration and combustion, but it is also a major component in many other crucial organic molecules that make up a living organism; for example, carbohydrates, proteins, fats all comprise oxygen in some amount. Oxygen has its use not only in terms of sustainability of life but also in recreational activities. For example, scuba divers depend upon artificially produced oxygen for underwater respiration. Even the mountaineers climbing much higher altitudes require a supply of artificial dioxygen in oxygen cylinders. Strangely enough, oxygen also has mild euphoric effects, due to which oxygen bars are quite popular in the United States. Apart from the above-mentioned, oxygen also has industrial applications, like smelting of iron ore into steel. This is a process in which dioxygen is administered into molten iron to remove impurities.
This process consumes about 55% of commercially produced oxygen.
Carbon dioxide is a trace gas with a concentration of just about 0.04%. The gases which are present in the atmosphere in very small amounts are known as trace gases. It has the chemical symbol CO2 and atomic number 6. Carbon dioxide is produced through respiration and also through the decomposition of organic materials. It is also produced through some natural sources like geysers, volcanoes, and hot springs. During the combustion of petroleum and natural gases, carbon dioxide is evolved. CO2 has a variety of applications. It is used in the food industry as an additive in order to regulate acidity. It is used in soft drinks and some candies. It is also used in fire extinguishers. We know that oxygen is required for combustion, so when we use carbon dioxide to extinguish a fire, it surrounds the fire and cuts off the supply of oxygen required for burning and hence quenches the fire. It is an important ingredient in the production of the fertilizer, urea. It is also used as a refrigerant during transportation as well as storage of frozen foods.
Even though carbon dioxide is a trace element, its amount in the air is constantly increasing, leading to what is known as air pollution. Various human activities like deforestation, burning of fossil fuels, and industrialization lead to tremendous amounts of carbon dioxide emission in the atmosphere. It causes lung diseases as well when inhaled in large quantities. It is a greenhouse gas which means that it absorbs and emits harmful ultraviolet light, thus, increasing the surrounding temperature. This increase in atmospheric temperature on a much larger scale is what is commonly known as global warming.
The most abundant, pure component of air is nitrogen, with a concentration of 78%. It has the symbol N and atomic number 7. Nitrogen is produced through a process called nitrogen fixation, which is a continuous cycle between living organisms and the atmosphere. It is also produced in industries by fractional distillation of air in its liquid form. Dinitrogen is a molecule of two nitrogen atoms bonded by a strong triple bond. Due to the triple bond, the decomposition of N2 is difficult and hence the process of its decomposition, which includes processes like exploding, produces a huge amount of useful energy. Nitrogen is present in living organisms in classes like nucleic acid, amino acids. Artificially produced nitrogen is also a very important component in fertilizers. Nitrogen also has its applications in the field of medicine, primary usage being in various drugs and even in antibiotics. Nitrogen is a non-toxic gas, but when it is emitted in an enclosed area, then it can displace oxygen which can lead to a situation of asphyxia.
FAQ Air chemistry and physics
FAQ Air chemistry and physics
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