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प्रश्न
Write the β-decay of tritium in symbolic form.
उत्तर
The β-decay of tritium is shown below
\[\ ^{3}_{1}{H} \to ^{ 3}_{2}{ He} + e^- + \bar{{v_e}}\]
It converts into a helium-3 nucleus by releasing an electron (or β particle) and an antineutrino.
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संबंधित प्रश्न
For the `beta^+` (positron) emission from a nucleus, there is another competing process known as electron capture (electron from an inner orbit, say, the K−shell, is captured by the nucleus and a neutrino is emitted).
\[\ce{e+ + ^A_Z X -> ^A_{Z - 1}Y + \text{v}}\]
Show that if `beta^+` emission is energetically allowed, electron capture is necessarily allowed but not vice−versa.
Consider the D−T reaction (deuterium−tritium fusion)
\[\ce{^2_1H + ^3_1H -> ^4_2He}\]
Consider the radius of both deuterium and tritium to be approximately 2.0 fm. What is the kinetic energy needed to overcome the coulomb repulsion between the two nuclei? To what temperature must the gas be heated to initiate the reaction? (Hint: Kinetic energy required for one fusion event =average thermal kinetic energy available with the interacting particles = 2(3kT/2); k = Boltzman’s constant, T = absolute temperature.)
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m (198Au) = 197.968233 u
m (198Hg) =197.966760 u
Write the basic nuclear process underlying β+ and β– decays.
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(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.)
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(b) `""_8^19O → _9^19F+`
(c) `""_13^25Al → ""_12^25Mg+`
