What is the nuclear energy
Electric energy by nuclear source is obtained through the reaction heat of the fuel (uranium) using the basic principle of how a conventional thermal factory works, which is always the same: the fuel burn produces heat that boils the water from a boiler, producing vapor. The vapor moves an engine that starts a generator, and this generator produces electricity. To understand about the released energy in the nuclear reaction is necessary to know more about the atom.
Atoms are lighter or heavier depending on the number of particles comprising it. The lighter atom known is the hydrogen atom and the heavier is the uranium atom.
An atom is comprised of a nucleus and smaller particles that gravitate around the nucleus. These particles are called electrons; they are very light and have a negative electric charge. Inside the nucleus, there are two types of particles, called protons and neutrons.
The number of protons is always equal to the number of electrons, but their charge is positive. As for the neutrons, these vary in number and the more numerous the heavier the atom. They have no electric charge; they are neutral, as the name indicates.
Although we know that atoms form everything existing in nature, we will only study the atoms of the element called uranium.
To differentiate them, we use the chemical symbol of the element and a number, according to the atomic weight - isotope U-234, isotope U-235 and isotope U-238.
The shock of a free neutron with the isotope U-235 causes the nucleus division of such isotope into two parts - another two atoms - generating a relatively high release of energy. This phenomenon is called nuclear fission.
The nuclear fission causes the transformation of matter into energy, through the division of the isotope U-235.
When the U-235 isotope fission occurs, the nucleus is divided into two parts forming two new elements, and from that 2 or 3 neutrons are released that in turn, may collide with another U-235 nucleus leading to another fission, new elements are formed, causing a sequence of fissions called nuclear chain reaction.
In nature, only the U-235 is capable to fission and therefore to sustain a chain reaction.
The use and the control of this released energy is carried out inside nuclear reactors, which in the nuclear power plants have the same role as the boiler in the ordinary thermal plants.
So as to optimize the nuclear reactions, the uranium is enriched before its use in the reactors. This operation comprises simply the increase of the level of U-235 isotope (the only one that fissions) in the isotope mixture of the natural uranium (U-234, U-235 and U-238).
Among the advantages and contributions presented by the use of nuclear energy instead of the conventional thermal plants we can state that, when used for the production of electric energy, it is a source of energy that does not emit any gas of greenhouse effect (carbon dioxide, methane, nitrous oxide and others) and no gas causing acid rain (sulfur dioxide, nitrogen oxides).
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