Question

Consider a radioactive nucleus $$A$$ which decays to a stable nucleus $$C$$ through the following sequence:
$$A\rightarrow B+C$$
Here $$B$$ is an intermediate nuclei which is alo radioactive. Considering that there are $${N}_{0}$$ atoms of $$A$$ initially, plot the graph showing the variation of number of atoms of $$A$$ and $$B$$ versus time.

Answer 1

Let us consider that in sample $$A$$ initially at $$t=0$$ there are $${N}_{0}$$ atoms of $$AB$$ and atoms of $$B$$ are zero initially.
When $$A$$ decay to $$B$$ the number of radioactive atoms of $$A$$ decreases and of $$B$$ increases
When a rate of decay of $$A$$ decreases to a lower value, then the number of radioactive atoms of $$B$$ becomes maximum. After this the radio-active atoms and rate of decay of $$B$$ decreases. Finally, the number of radioactive atoms of sample $$A$$ and $$B$$ becomes very low near to zero.