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प्रश्न
(a) Write the basic nuclear process involved in the emission of β+ in a symbolic form, by a radioactive nucleus.
(b) In the reactions given below:
(i)`""_16^11C->_y^zB+x+v`
(ii)`""_6^12C+_6^12C->_a^20 Ne + _b^c He`
Find the values of x, y, and z and a, b and c.
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उत्तर
(a)
The basic nuclear process involved in the emission of β+ in a symbolic form, by a radioactive nucleus
p →n + β++ v
For a beta-plus decay, a proton transforms into a neutron within the nucleus, according to the above reaction.
(b)
(i)
`""_6^11C->_y^zB+x+v`
`=>""_6^11C->_5^11B+_1^0beta+100`
The corresponding y and z are 5 and 11, respectively. The x is the positron
(ii)
`""_6^12C+_6^12C->_a^20 Ne +_b^c He`
⇒
`""_6^12C+_6^12C->_10^20Ne+_2^4He`
The corresponding values of a, b and c are 10, 2 and 4, respectively.
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संबंधित प्रश्न
How is the mean life of a given radioactive nucleus related to the decay constant?
The Q value of a nuclear reaction A + b → C + d is defined by
Q = [mA+ mb − mC − md]c2 where the masses refer to the respective nuclei. Determine from the given data the Q-value of the following reactions and state whether the reactions are exothermic or endothermic.
\[\ce{^12_6C + ^12_6C ->^20_10Ne + ^4_2He}\]
Atomic masses are given to be
`"m"(""_1^2"H")` = 2.014102 u
`"m"(""_1^3"H")` = 3.016049 u
`"m"(""_6^12C)` = 12.000000 u
`"m"(""_10^20"Ne")` = 19.992439 u
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