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What is Air Pollution?

 

 

Air Pollution, is the addition of harmful substances to the atmosphere resulting in damage to the environment, human health, and quality of life. This kind of pollution is caused apparently everywhere; at home, at school, in industries, etc. it promotes all kinds of sicknesses like lung cancer and shortens the life span of man. It also kills plants, animals and ecosystems that live in the environment. The air gets polluted through acid rain, radioactivity, ozone, and the release of poisonous gases into the atmosphere. Factories and transportation depend on huge amounts of fuel--billions of tons of coal and oil are consumed around the world every year. When these fuels are burnt, they introduce smoke and other less visible by-products into the atmosphere.

 

ACID RAIN

 

Acid rain is a form of land pollution. Snow can also contain acid. It is normally a precipitation and contains a heavy concentration on sulphuric and nitric acids. In many areas of North America and Europe, this is a problem. Vehicles, certain industrial operations, and electric power plants that burn fossil fuels release sulphur dioxide and nitrogen oxides into the atmosphere. When these gases are released into the atmosphere, they combine with the water in the clouds and it forms acids the gases sulphur dioxide and nitrogen oxides into the atmosphere, where they combine with water vapour in clouds to form sulphuric and nitric acids. Thus, these acids come back down to earth in the form of rain but instead of ordinary rain, its acid rain. It becomes harmful to human life because it gets into rivers, streams, lakes and other drinking sources. Also, it may affect the plant growth of some crops and other plants.

 

 

 

RADIOACTIVE POLLUTANTS

 

This is and always has been part of our environment naturally. One specific example of this is the atomic bomb. Since the first atomic bomb was made in August 1945, there has been awareness of a treat to the environment, in the sense that more nuclear weapons are being produced. As a result, the atmosphere is being filled with more nuclear waste (dust and smoke) which is harmful to human life. These things, explosion after explosion, will block the suns light rays and its heat causing the temperatures to drop. Radioactives also have a life span of half-life or more meaning that after an explosion, some of the energy would still be hanging around for over a thousand years and this is dangerous.

 

 

 

OZONE

 

Like ordinary oxygen gas (O2), the ozone contains oxygen atoms (O3), but is has a distinct type of bonding. Its bonding is three atoms per molecule. This gas gives the atmosphere and odour after thunderstorms. It is manufactured by passing an electric discharge through the air or through oxygen.  Also by releasing chemicals like chlorofluorocarbons (CFCs), formerly used as refrigerants (notably in air conditioners) and other gases like nitrous oxide from fertilizers and the pesticide methyl bromide into the atmosphere.  Ozone, is used to purify, bleach, deodorize, and other reactions that result in oxidation and reduction. Small amounts that occur naturally in the ozone layer absorb ultraviolet (UV) radiation. When the ozone level is high, it shows the presence of carbon monoxide and other pollutants in high levels.

The molecules of the chlorofluorocarbons are vitally indestructible until they reach the stratosphere. Chlorine atoms are released into the atmosphere through intense ultraviolet radiation (UV). The UVs break the CFC molecules apart and that causes chlorine to get into the atmosphere. These chlorine atoms react with the ozone (O3). Chlorine just acts as a catalyst to the reaction. It has been researched that one chlorine atoms can destroy up to 100,000 ozone atoms in the stratosphere.

Due to the constant release or these chemicals into the atmosphere, we are loosing the ozone layer day after day because it is getting thinner. According to scientists in the Antarctic region, the ozone vanishes almost entirely for a few weeks every year.  Because of the constant release of these gases into the atmosphere, there is a belief that not all of the gases have reacted with the ozone. After some years to come, they will react and then human life will be exposed to an increase in skin cancers, more cataracts (clouding of the lens of the eye), and reduced yields of some food crops.

 

 

 

FOSSIL FUELS

 

Fossil fuels are used by industries and some vehicles. It is also used domestically. Some of these fuels are coal, petroleum, and shale oil. They are all made up of carbon and were formed from remains of dead plants and animals that were in existence millions of years back. They are burnt to provide heat or even steam to produce electricity for a generator.  Fossil fuels supply nearly 90% of all the energy used by industrially developed nations.

 

 

 

SMOG

 

The word SMOG is a combination of the words, smoke and fog. This word came into existence in the early 19th century. It can also b described as intense local pollution that is usually trapped by a thermal invasion. In the 19th century, London used to burn coal to produce heat energy and to produce fuel for trains, cars and other vehicles that ran on fuel. All these gave off their exhaust into the atmosphere. After a time of continuous release, the atmosphere got so polluted. Street lights had to be turned on during the day because the smog had darkened the midday light. It still happens today. People died and others fell ill. It was worse and is worse for people who suffer from heart diseases and asthma. They find it hard for them to breathe and they end up dying. In 1948 in the steel-mill town of Donora, Pennsylvania, intense local smog killed 19 people. In 1952 in London about 4,000 people died in one of the notorious smog events known as London Fogs; in 1962 another 700 Londoners died.

Burning gasoline in motor vehicles is the main source of smog today.  Smog also contains ozone which is also poisonous to the lower atmosphere. Sulphurous smog also occurs as a result of the use of sulphur- bearing fossil fuels, like coal, and are aggravated by dampness. Smog that occurs without smoke or fog is called photochemical smog. It is caused by the reaction between the sun and its heat and nitrogen oxides and the hydrocarbon vapours that are emitted from the vehicles and other sources of exhaust. This reduces visibility, causes plant damage, irritates the eye and even distresses respiration.

 

 

 

NITROGEN GASES

 

It is a colorless, odourless, tasteless gas in the atmosphere. The atmosphere is made up of about 78% of it and it is consistent for all human lives. It is also useful because liquefies the air and it dilutes other gases to reduce the risks of pollution and contamination. Ammonia, which is made up of nitrogen, is the starting material for most other nitrogen compounds (especially nitrates and nitrites), whose main uses are in agricultural fertilizers and explosives.

Nitrogen gas forms several oxides like nitrous oxide; nitric oxide (NO). It has been researched that it plays and major role in physiology. Also, nitrogen dioxide (NO2) and other forms of nitrogen gases (including N2O3 and N2O5) cause air pollution, especially when they react with the suns light and heat. Other compounds include the nitrides, exceptionally hard materials made from nitrogen and a metal like cyanides, pollute the atmosphere.

 

 

 

NITROGEN FIXATION  

 

Nitrogen fixation is a natural or industrial process that causes free nitrogen in the air to combine chemically with other elements to form more reactive nitrogen compounds such as ammonia, nitrates, or nitrites. Soil micro organisms, such as Rhizobium bacteria living in root nodules of legumes, are responsible for over 90% of all nitrogen fixation. Nitrogen is essential for the metabolism of both plants and animals, but they cannot live on nitrogen gas. Nitrogen fixation invades the roots of the plants with bacteria and infects the plants by contaminating it. Within the nodules the bacteria convert free nitrogen to nitrates, which the host plant uses for its development. Nitrogen fixation by bacteria associated with legumes is of prime importance in agriculture. Before the use of synthetic fertilizers in the industrial countries, usable nitrogen was supplied as manure and by crop rotation that included a legume crop.

  

 

 

COAL

 

Coal is a material, black or brown in colour, which is burnt to produce heat. It has two types; bituminous and anthracite. It has been identified as one of the most important fossil fuel in many parts of the world today. Coal is formed by heat and pressure over millions of years on vegetation deposited in ancient shallow swamps. Coal has long been used as fuel, for power generation, for the production of coke, and as a source of various compounds used in synthesizing dyes, solvents, and drugs. The search for alternative energy sources has revived interest in the conversion of coal into liquid fuels similar to oils and countries that use a lot of oil intended to use it the most.

 

 

 

BITUMINOUS COAL

 

Bituminous coal is the soft coal and is very common. It is dark brown to black and has a relatively high heat value but not as high as anthracite. It is very common and the cheapest coal available, it has long been used for steam generation in electric power plants and industrial boiler plants. Certain varieties are also used to make coke, a hard substance of almost pure carbon that is important for smelting iron ore. Burning large quantities of bituminous coal releases large quantities of sulphur into the atmosphere and that contributes to air pollution and produces acid rain.

 

 

 

ANTHRACITE

 

Anthracite isnt as soft as bituminous coal. Rather, it is hard coal. It  contain more fixed carbon than any other form of coal and the lowest amount of volatile ,which is a quickly evaporating, material giving it the greatest heat value. It turns out to be the most valuable of the coals, and is scarce. Surprisingly, it makes up less than 2% of all coal reserves in the U.S., with most of the known deposits occurring in the East. Anthracites are black and have a brilliant, almost metallic lustre. People use them as decorative when they are hard, brittle and polished. They are difficult to ignite but burn with a pale-blue flame and require little attention to sustain combustion. They are sometimes mixed with bituminous coal to heat commercial buildings but are seldom used alone for heating because of their high cost.

 

INDOOR AIR POLLUTION

 

This can be the most dangerous form of air pollution because you are not aware of the dangers. Some of these include tobacco smoke; radon, and other invisible radioactive gas that enters homes from the ground in some regions. Chemicals that are released from synthetic carpets and furniture, pesticides, and household cleaners can all be classified as indoor pollution. These chemicals, when inhaled for long periods of time, can give cancer to the lungs. Pollutants may accumulate to reach much higher levels than they do outside, where natural air currents disperse them. It has been researched that indoor air levels of many pollutants can be 2 to 5 times greater than those outside. Thus the risk of contamination is higher because people spend 90 percent of their time living, working, and playing indoors. Inefficient or improperly vented heaters are particularly dangerous.