Nuclear fission is the phenomenon of splitting of an unstable nucleus of a heavy atom(e.g.-uranium,plutonium or thorium,U-235)into two medium weight nuclei with liberation of an enormous amount of energy.The fission is carried out by bombarding the heavy nuclei with suitable projectiles,usually slow neutrons.
The phenomenon was discovered in the year 1939 by two German scientists Otto Hahn and Fritz Strassman. The bombarded U-235 with low energy neutrons, called thermal neutrons.Just as a glass ball when hit with a hammer may shatter in different sizes,U-235 nucleus splits up broadly into two groups of nuclei:
(1) a heavy group of nuclei,with mass number in the range A=130 to A=149.
(2) a light group of nuclei,with mass number in the range A=85 to A=104.
out of these, the most prominent products and Barium with mass number 139 and Krypton with mass number 94.three neutrons(or in some cases two neutrons)are produced along with enormous amounts of energy in the form of gamma rays ; heat energy and light energy.Fig. 1 represents line diagram of the fission of U-235.As the fission produces two neutrons or three neurons,the third neutron is shown with a light shade.
In the form of a nuclear reaction,we represent nuclear fission of U-235 as follows :
The phenomenon was discovered in the year 1939 by two German scientists Otto Hahn and Fritz Strassman. The bombarded U-235 with low energy neutrons, called thermal neutrons.Just as a glass ball when hit with a hammer may shatter in different sizes,U-235 nucleus splits up broadly into two groups of nuclei:
(1) a heavy group of nuclei,with mass number in the range A=130 to A=149.
(2) a light group of nuclei,with mass number in the range A=85 to A=104.
out of these, the most prominent products and Barium with mass number 139 and Krypton with mass number 94.three neutrons(or in some cases two neutrons)are produced along with enormous amounts of energy in the form of gamma rays ; heat energy and light energy.Fig. 1 represents line diagram of the fission of U-235.As the fission produces two neutrons or three neurons,the third neutron is shown with a light shade.
Figure. 1
In the form of a nuclear reaction,we represent nuclear fission of U-235 as follows :
The materials which can be fissioned even with low energy neutrons are called fissile materials.
These materials are used as fuels for nuclear power plants and also for production of atom bombs.
The amount of energy produced in nuclear fission is enormous.One kilogram of U-235,on fission,produces as much energy as 2500 tons of coal produces on burning.
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