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Nuclear Energy
Energy released through the splitting or the combining of atomic nuclei.
Significant amounts of heat are released from interaction of the atomic nuclei.
Nuclear energy, which is different from chemical reactions, which only involve
the orbital electrons of an atom. The reaction stems from the equation E=mc²,
where E, energy is equivalent to m, mass and c, the speed of light.
Since the 1800’s, the main fuel source was energy stored in wood. The Industrial
Revolution altered the chief fuel source, and fossil fuels, coal and petroleum
were used as an alternate energy source. Many byproducts of these chemical
reactions can produce greenhouse gas emissions, which can cause filthy air,
disrupt the Earth’s climate, and shower acid rain.
Fission
This is one of the ways that nuclear energy may be released: by the dividing of
a heavy nucleus. Atoms of certain elements split, producing heat. Uranium-235
being one of these contains 235 particles of protons and neutrons. Free neutrons
move about passing through or colliding with nuclei. Occasionally a neutron
splits, or fissions a uranium-235 nucleus and this process creates energy, or
heat and also produces on average 2.5 neutrons, but these are quickly lost so no
chain reaction may occur. The products produced through this reaction are of the
following: cesium-140, rubidium-93, 2-3 neutrons, and 200MeV(million electron
volts, 1.6 kilowatt is equivalent to 10 electron volts).
A self sustained fission reaction, which is found in the nuclear reactor’s core,
is when on average one fission reaction sustains to a new fission reaction, the
heat produced is used to generate electrical energy. When one fission reaction
results in more than one other fission reaction produced, then an uncontrolled
fission chain-reaction occurs. Massive amounts of heat are produced within a
tiny fraction of a second, and this is the base to nuclear weapons.
The reason why many fission reactions occur within the Earth’s crust in
concentrations of uranium ore, is because in naturally occurring uranium only
0.71 is uranium-235, while the rest is a non-fissile isotope uranium-238. If by
some chance there is a large concentration of uranium-235 found in an ore, there
is still a highly likely chance that no chain reaction would occur as the
neutron’s motion is slowed down through the collision of other light nuclei,
hydrogen, carbon, or deuterium. The use of the light nuclei is the base to
nuclear reactors.
Fusion
Fusion is the process of the combining hydrogen or isotopes of hydrogen. The
products produced with this reaction are helium, 3.2 MeV, and 1 USE ONE INSTEAD
OF 1 neutron. An important factor in fusion reactions, is that there are no
radioactive byproducts, like in a fission reaction. The essential point of a
fusion reaction though, is that the reaction requires a temperature of tens of
millions of degrees, because of this fusion is also known as a thermonuclear
reaction. The energy released during fusion is much greater than a fission
reaction, as well the fuel for fusion are in readily available amounts.
One would wonder why currently, that nuclear fusion is not used as an
electricity source for the world. The temperatures needed for a fusion reaction
are tens of millions of degrees, and these are only attainable through a fission
bomb. Obviously a fission bomb cannot be used to trigger a fusion reaction for
the sake of supply energy to citizens.
An ordinary hydrogen reaction, which occurs in stars, is much too slow to be of
any use on earth. Scientist have found that deuterium and tritium, heavier
isotopes of hydrogen, allow for a faster reaction, which only takes about 0.1
seconds. At this temperature, ordinary states of matter are no longer solid but
instead plasma, which consists of electrons and charged atoms. No ordinary solid
is able though to contain such high temperatures, so upon using magnetic and
electrical properties of plasma, scientists have been able to create a ‘magnetic
bottle’ to contain the huge amount of heat produced from the plasma.
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