Class 12th Physics 2017 Set1 Delhi Board Paper Solution
A radioactive nucleus A undergoes a series of decays as given below:
The mass number and atomic number of A2 are 176 and 71, respectively. Determine the mass and atomic numbers of A4 and A.
In α-decay, the atomic number is decreased by 2 units and mass number decreases by 4 units. In β-decay, the atomic number increases by 1 unit but mass number does not change. In γ-decay there is no change in mass and atomic number.
Therefore, the mentioned radioactive decays will proceed as below.
So, A4 has mass number 172 and atomic number 69.
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