Modern Physics 3 Question 32
33. In the uranium radioactive series, the initial nucleus is ${ } _{92}^{238} U$ and the final nucleus is ${ } _{82}^{206} Pb$. When the uranium nucleus decays to lead, the number of $\alpha$-particles emitted is … and the number of $\beta$-particles emitted is ….. .
(1985, 2M)
Show Answer
Solution:
- Number of $\alpha$-particles emitted, $n _1=\frac{238-206}{4}=8$ and number of $\beta$-particles emitted are say $n _2$, then
$$ \begin{array}{rlrl} \therefore & 92-8 \times 2+n _2 & =82 \\ n _2 & =6 \end{array} $$
