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.