In decay mass number decreases by unit and atomic number decreases by unit.
In decay mass number does not change but atomic number increases by unit.
In decay mass number does not change but atomic number decreases by unit.
So for
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Number of alpha particle . Due to alpha particle, atomic number should decrease by but it has decreased by only, therefore an additional decay is required, then net change in atomic number will be . Therefore, .
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Number of alpha particle . Due to alpha particle, atomic number should decrease by , but there is no change in atomic number, which means two additional decay is required, then net change in atomic number will be . Therefore, .
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Number of alpha particle . Due to alpha particle, atomic number should decrease by , but atomic number has increased by , which means three additional decay is required, then net change in atomic number will be . Therefore, .
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Number of alpha particle . Due to alpha particle, atomic number should decrease by , but atomic number has decreased by , which means one additional is required, then net change in atomic number will be . Therefore, .
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