Carbon Dioxide
The compound carbon dioxide (CO2) is now the subject of worldwide
attention as being a major component in the untoward concentration
of greenhouse gases in the earth's atmosphere. Before the start
of the industrial revolution, carbon dioxide concentration was
recorded at 280 parts per million or PPM but recent estimates
placed it at 375 PPM, a large increase because of man's industrial
activities and utter disregard for the environment.
If carbon dioxide becomes even denser, scientists warn, this
will most likely play havoc on climatic behavior due to global
warming. Carbon dioxide as a chemical compound is colorless, odorless
and tasteless and is 1.5 times heavier than air.
Flemish scientist Jan Baptist van Helmont discovered carbon dioxide
as a chemical compound from his earlier observations that the mass
of ash is very much lesser than the actual charcoal when burned
in a close container. During the 1750's Scottish physician Joseph
Black confirmed Helmont's observations to further reinforce previous
findings.
But, it was English chemist Joseph Priestly who initially published
a paper about the chemical compound. In 1823, Humphrey Davy and
Michael Faraday were the first to liquefy carbon dioxide at elevated
pressures and in 1834 Charles Thilorier gave the earliest description
of solid carbon dioxide or solid ice.
What is the importance of carbon dioxide?
Plants and other forms of vegetation need carbon dioxide to complete
its food production cycle. With water, sunlight and carbon dioxide,
photosynthesis takes place, which expels oxygen and moisture and
promotes growth.
In a properly controlled environment, such as a green house, it
was observed that levels of up to 500 PPM of carbon dioxide induce
rapid growth in plants while a low of 200 PPM stunts a plant's growth.
This phenomenon is also observed among areas where decaying vegetation
is present, because this likewise initiates plant growth.
Carbon dioxide finds use in commercial applications, particularly
in the production of carbonated beverages as it provides sparkle
to our favorite drinks. It also serves as ingredient, which allows
the lift of yeast or baking powder and causes bread to rise. A carbon
dioxide compound is likewise used to treat water, manufacture aspirin
and lead based paint pigments, as well as in the preparation of
sodium carbonate.
In industrial applications, carbon dioxide is used over fire extinguishers
as an effective fire retardant; also as pressurizing medium and
propellant in food aerosol cans, target pistols and as inflating
medium for life rafts. Since carbon dioxide is relatively inert
and manifests a non-reactive atmosphere, it is used in packaging
food such as coffee beans which spoil easily. A modified version
of carbon dioxide is used as refrigerant in air-conditioning or
cooling installations and also in residential and medical refrigerators
and freezers.
How is carbon dioxide produced?
The main source for carbon dioxide that permeates the atmosphere
is the burning of fossil fuels (gas, oil, coal). Thus, excessive
use of it increases the accumulation of greenhouse gases. Anything
that burns produces a corresponding amount of carbon dioxide, from
forest fires to automobile acceleration to jet engines and even
small grass fires.
Decaying vegetation also contributes to carbon dioxide accumulation.
Man and animals add to the pollution of the environment, because
as we exhale oxygen we expel carbon dioxide. The main concentration
of excessive carbon dioxide emissions lie with manufacturing plants
and power plants, especially those that are run on fossil fuels.
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