Sulfur cycle - Transtutors

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22 Φεβ 2014 (πριν από 3 χρόνια και 8 μήνες)

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Sulphur is basically an element which can be enlisted under the
groups of chemicals. It is symbolized with ‘S' and the number of
atoms that are present in it is
16.
Under normal circumstances, the
atoms of sulphur always try to form a cycle which contains octatomic
molecules. Then the chemical representation of sulphur is done by
S
8
. The color of a natural sulphur element is yellow. In chemical
reaction sulphur takes part as an oxidant. Sometimes it reacts as a
reducing agent too.
That is the reason behind every sulphur cycle.

Sulphur is found in almost every living body. Sulphur

is not destructible as the atoms are existed in earth's

environment. There are many processes which use

sulphur element for chemical reaction. Thus sulphur

atoms are recycled again and again and the effects

of this cycle spread in the four spheres of our

environment. Except this ‘biogeochemical cycle', we

are also accustomed with carbon cycle as well as

nitrogen cycle.













ISOTOPES OF SULPHUR



Sulfur has 25 known
isotopes
, four of which are
stable:
32
S (95.02%),
33
S (0.75%),
34
S (4.21%), and
36
S
(0.02%). Of those four, two (
32
S, light and
34
S, heavy)
comprise (99.22%) of S on Earth. The vast majority
(95.02%) of S occurs as
32
S with only 4.21% in
34
S.




PROCESSES IN THE SULPHUR CYCLE




The
main source
of sulphur
is
in the
air as different compounds of sulphur are
present

there.
‘Methane Sulphonic acid' is present in the air and it is another source of sulphur.

Except
this sulphur dioxide SO
2

is
a common
source of sulphur cycle. These touch the

surface
of the earth during the time of raining. Plants need water from soil for
preparing their food. While doing this it also takes the compounds of sulphur that are
mixed with soil as well as ground water. After the death of the plant all the consumed
sulphur
returns back
to soil or eaten up by the vegetarian.


The
sulfate anions as well as dissolved
hydrogen
sulphide

H
2
S
gas act as the source of
sulphur inside the ocean. The drinking water also contains sulphur in various forms.
Except hydrogen sulfide we can also find sulfate as well as sulphur in its elemental form
in the fresh water. It has
already been
discussed
that land
is the biggest source of
sulphur. Other than this the H
2
S gas is processed by the bacteria.





Sulphur dioxide is created by the help of phytoplankton in the sea. Both of these gases
again go into the environment for continuing the chemical cycle. Inside the earth's
surface the biggest source of sulphur is available. They are known as gypsum and pyrite.
The first is a compound made of calcium, sulphur and oxygen. In pyrite except sulphur
we will get iron. We can't pull out the gases of sulphur from the sulphur cycle as it is
completely fixed. In some cases, the chemical reactions of this cycle help the under
water volcanoes for opening up. In the deep sea, where water contains low pH with a
great amount of temperature, sulphur cycle provides support for living.




Both the living beings and nature are nourished by the effect of sulphur cycle. For growth
animal needs proteins as well as vitamins. These two substances are made of sulphur and
some other components. Not only proteins but also enzymes are needed by the plants.
Here sulphur plays an important role as an activator. The dissolved
sulpher

in water is
absorbed by the plants during photosynthesis. When the vegetarian animals eat these
plants, then
sulpher

is also consumed by them. We can found the oxidized
sulphate

in
the polluted as well as natural water.



This rainwater is associated with some formation of rocks and caused the certain
change in climate. Because of its acidic tendency it increases the rates of
dentrification
.
It also enhances the ‘acid precipitation'. In comparison to the other
sulpher

compounds, life cycles of air soluble
sulpher

compounds are not long. At most a cycle
continues for a few days. These cycles leave a great impact on sedimentation as well as
erosion.


The most dangerous effect can be seen at the time of volcano eruption. Through a vent
all the lava, rock fragments, hot vapor and SO
2

gas have been erupted from the earth's
crust. Thus the atmosphere gets polluted. Not only that but also the industrial garbage
cause the presence of
sulpher

in air. Human being is most responsible for the activities
of
sulpher

cycle. When they burn the fossil fuels, a large number of
sulpher

is
generated.
Sulpher

aerosols are responsible for breathing problem.




DIAGRAM OF SULPHUR CYCLE