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प्रश्न
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.
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उत्तर
(a) Amount of hydrogen, m = 1 kg = 1000 g
1 mole, i.e., 1 g of hydrogen `(""_1^1"H")` contains 6.023 × 1023 atoms.
∴ 1000 g of `""_1^1"H"` contains 6.023 × 1023 × 1000 atoms.
Within the sun, four `""_1^1"H"` nuclei combine and form one `""_2^4"He"` nucleus. In this process 26 MeV of energy is released.
Hence, the energy released from the fusion of 1 kg `""_1^1"H"` is:
`"E"_1 = (6.023 xx 10^23 xx 26 xx 10^3)/4`
`= 39.1495 xx 10^26 " MeV"`
(b) Amount of`""_92^235"U"` = 1 kg = 1000 g
1 mole, i.e., 235 g of `""_92^235"U"` contains 6.023 × 1023 atoms.
∴ 1000 g of `""_92^235"U"` contains
`(6.023 xx 10^23 xx 1000)/235 "atmos"`
It is known that the amount of energy released in the fission of one atom of `""_92^235"U"` is 200 MeV.
Hence, energy released from the fission of 1 kg of `""_92^235"U"` is:
`"E"_2 = (6 xx 10^23 xx1000 xx 200)/235`
`= 5.106 xx 10^26 " MeV"`
`therefore "E"_1/"E"_1 = (39.1495 xx 10^26)/(5.106 xx 10^26) = 7.67 ~~ 8`
Therefore, the energy released in the fusion of 1 kg of hydrogen is nearly 8 times the energy released in the fission of 1 kg of uranium.
संबंधित प्रश्न
Suppose, we think of fission of a `""_26^56"Fe"` nucleus into two equal fragments `""_13^28"Al"`. Is the fission energetically possible? Argue by working out Q of the process. Given `"m"(""_26^56 "Fe") = 55.93494 "u"` and `"m"(""_13^28 "Al") = 27.98191 "u"`.
A 1000 MW fission reactor consumes half of its fuel in 5.00 y. How much `""_92^235"U"` did it contain initially? Assume that the reactor operates 80% of the time, that all the energy generated arises from the fission of `""92^235"U"` and that this nuclide is consumed only by the fission process.
If three helium nuclei combine to form a carbon nucleus, energy is liberated. Why can't helium nuclei combine on their own and minimise the energy?
The mass of a neutral carbon atom in ground state is
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(b) a neutron is an unstable particle
(c) a neutron does not exert electric repulsion
(d) Coulomb forces have longer range compared to the nuclear forces.
Calculate the energy released by 1g of natural uranium assuming 200 MeV is released in each fission event and that the fissionable isotope 235U has an abundance of 0.7% by weight in natural uranium.
Calculate the Q-value of the fusion reaction 4He + 4He = 8Be. Is such a fusion energetically favourable? Atomic mass of 8Be is 8.0053 u and that of 4He is 4.0026 u.
(Use Mass of proton mp = 1.007276 u, Mass of `""_1^1"H"` atom = 1.007825 u, Mass of neutron mn = 1.008665 u, Mass of electron = 0.0005486 u ≈ 511 keV/c2,1 u = 931 MeV/c2.)
Calculate the energy that can be obtained from 1 kg of water through the fusion reaction 2H + 2H → 3H + p. Assume that 1.5 × 10−2% of natural water is heavy water D2O (by number of molecules) and all the deuterium is used for fusion.
(Use Mass of proton mp = 1.007276 u, Mass of `""_1^1"H"` atom = 1.007825 u, Mass of neutron mn = 1.008665 u, Mass of electron = 0.0005486 u ≈ 511 keV/c2,1 u = 931 MeV/c2.)
Distinguish between nuclear fission and fusion giving an example of each.
A heavy nucleus P of mass number 240 and binding energy of 7.6 MeV per nucleon splits into two nuclei Q and R of mass number 110 and 130 and binding energy per nucleon of 8.5 MeV and 8.4 MeV respectively. Calculate the energy released in fission.
In a nuclear reactor, moderators slow down the neutrons which come out in a fission process. The moderator used have light nuclei. Heavy nuclei will not serve the purpose because ____.
If in nuclear fusion process the masses of the fusing nuclei be m1 and m2 and the mass of the resultant nucleus be m3, then:
Power generated by a nuclear reactor is given by P = n E / t. Here n represents:
\[\ce{^290_80X ->[\alpha] Y ->[e+] Z ->[\beta-] P ->[e-] Q}\]
In the nuclear emission stated above, the mass number and atomic number of the product Q respectively, are:
