“Who will tell whether one happy moment of love or the joy of
breathing or walking on a bright morning and smelling the fresh air, is not
worth all the suffering and effort which life implies.”
-
Erich Fromm
Can you imagine how life should be like without air?
The air, also known as atmosphere is a mixture of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat
retention (greenhouse
effect), and
reducing temperature extremes between day and night (the diurnal temperature variation).The air is used in breathing and
photosynthesis.
Air also contains a variable
amount of water
vapor, on average around 1%. Although air content and atmospheric pressure vary at different layers,
air suitable for the survival of terrestrial
plants and terrestrial animals currently is only known to
be found in Earth's troposphere(0 to 12km/ 0 -7miles from the surface of the
Earth) and artificial atmospheres.
What then constitutes air? I am going to focus on the top three constituents.
The top three constituents are nitrogen, oxygen and argon.
NITROGEN
Nitrogen is an
odorless, tasteless, colorless nonmetallic chemical element which appears in
great abundance in the Earth's atmosphere. It also appears in a number of other
compounds, and is a vital component of life on Earth for many organisms. In
addition to inhaling nitrogen with every breath,
most organisms also consume it in their food on a daily basis. Approximately
4/5 of the Earth's atmosphere is made up of nitrogen,
and the element is the seventh most abundant in the universe. Nitrogen is a
chemical element with symbol N and atomic number 7.
Nitrogen occurs in all organisms,
primarily in amino acids (and thus proteins) and also in the nucleic acids (DNA
and RNA). The human body contains about 3% by mass of
nitrogen, the fourth most abundant element in the body after oxygen, carbon,
and hydrogen. Nitrogen is an essential building block of amino and nucleic acids, essential to life on Earth.
OXYGEN
Oxygen is a chemical element with symbol O and atomic number 8. Oxygen is the most abundant chemical element by mass in the
Earth's biosphere, air, sea and land. Oxygen is the third most abundant
chemical element in the universe, after hydrogen and helium. About 0.9% of the Sun's mass is oxygen. Oxygen constitutes 49.2% of the Earth's crust by mass. and is the major component of the
world's oceans (88.8% by mass). Oxygen gas is the second most common component
of the Earth's atmosphere, taking up 20.8% of its volume and 23.1% of its mass (some
1015 tonnes) Earth is unusual among the
planets of the Solar
System in having
such a high concentration of oxygen gas in its atmosphere: Mars (with 0.1% O
2 by volume) and Venus have far lower concentrations.
2 by volume) and Venus have far lower concentrations.
The
unusually high concentration of oxygen gas on Earth is the result of the oxygen cycle.
The main driving factor of the oxygen cycle is photosynthesis,
which is responsible for modern Earth's atmosphere. Photosynthesis releases
oxygen into the atmosphere, while respiration and decay
remove it from the atmosphere.
ARGON
Argon is a chemical element with symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas.[3] Argon is the third most
common gas in the Earth's atmosphere,
at 0.93% (9,300 ppm), making it approximately 23.8 times as abundant as the
next most common atmospheric gas, carbon dioxide (390 ppm). Nearly all of this
argon is radiogenic argon-40 derived from the decay of potassium-40 in the Earth's crust. In the
universe, argon-36 is by far the most common argon isotope, being the preferred argon isotope
produced by stellar nucleosynthesis in supernovas.
Since 2002, the American National Archives stores important national
documents such as the Declaration
of Independence and the Constitution
within argon-filled cases to retard their degradation.
Blue argon lasers are used in surgery to
weld arteries, destroy tumors, and to correct eye defects.
All said and done, it is clear we cannot
do without air, air is critically important for sustenance of life. The top
three gases in the air, nitrogen, oxygen and argon together constitute over 99%
of the air or atmosphere. Nitrogen is an essential building block of amino and
nucleic acid, essential to life on Earth. The human body contains oxygen. Argon
is used in surgery to weld arteries, destroy tumors, and to correct eye
defects.
Reference:
gardendigest.com
en.wikipedia.org
Comments
Post a Comment