Question

For the radioactive nuclei that undergo either $\alpha$ or $\beta$ decay, which one of the following cannot occur?

• A. Isobar of original nucleus is produced
• B. Isotope of the original nucleus is produced
• C. Nuclei with higher atomic number than that of the original nucleus is produced
• D. Nuclei with lower atomic number than that of the original nucleus is produced

Answer 1

The correct option is B Isotope of the original nucleus is produced

$\alpha$ decay reaction : ${}_Z^{A}X$ $\overrightarrow{}$ ${}_{Z-2}^{A-4}Y$ $+$ ${}_2^{4}He$ $\left(\alpha \right)$

In $\alpha$ decay, nucleus with lower atomic number than that of the original nucleus is produced

$\beta$ decay reaction : ${}_Z^{A}R$ $\overrightarrow{}$ ${}_{Z+1}^{A}P$ $+$ ${}_{-1}^{0}e$ $\left(\beta \right)$

In $\beta$ decay, nucleus with higher atomic number than that of the original nucleus is produced.

Also nuclei $R$ and $P$ are isobars of each other.

Hence, in $\alpha$ or $\beta$ decay reaction, Isotope of original nucleus in not produced.