Q. 305.0( 3 Votes )
Calculate and compare the energy released by a) fusion of 1.0 kg of hydrogen deep within Sun and b) the fission of 1.0 kg of 235U in a fission reactor.
Answer :
a) Mass of hydrogen, m = 1kg = 1000 g
Since,1 mole of hydrogen contains 6.023×1023 atoms which is equivalent to 1 g of hydrogen then, 1kg of hydrogen contains,
N = 6.023×1023×1000 = 6.023×1026 atoms
In sun, 4 hydrogen atoms, 
combine to form one helium atom, 
in fusion process which releases 26 MeV of energy.
Thus,
Energy released from fusion of 1kg of hydrogen is,
……………….(1)
= 
b) Mass of uranium, m = 1kg = 1000 g
Since,1 mole of Uranium contains 6.023×1023 atoms which is equivalent to 235 g of Uranium then, 1kg of Uranium contains,
N = 
During fission reaction of 1 atom of 
releases 200 MeV of energy.
Thus,
Energy released from fission of 1kg of Uranium is,
………..(2)
Divide (1) by (2) we get,
Hence, Fusion reaction occurred in Sun releases 8 times more energy than energy released during the fission reaction of Uranium.
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Bohr's Atomic Model46 mins
Four nuclei of an element undergo fusion to form a heavier nucleus, with release of energy. Which of the two- the parent or the daughter nucleus - would have higher binding energy per nucleon ?
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(b) 
(c) 
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