Question

A radioactive nucleus ${ }_{Z}^{ A } X$ undergoes spontaneous decay in the sequence
${ }_{ Z }^{ A } X \rightarrow _{z-1} B \rightarrow _{Z -3} C \rightarrow _{Z -2} D$, where $Z$ is the atomic number of element $X$. The possible decay particles in the sequence are :

• A. $\alpha, \beta^{-}, \beta^{+}$
• B. $\alpha, \beta^{+}, \beta^{-}$
• C. $\beta^{+}, \alpha, \beta^{-}$
• D. $\beta^{-}, \alpha, \beta^{+}$

Answer 1

Answer: (C)

${ }_{z} X ^{A} \rightarrow{ }_{z-1} B \left(\beta^{+}\right.$decay $)$
${ }_{z-1} B \rightarrow_{z-3} C (\alpha-$ decay $)$
${ }_{z-3} C \rightarrow{ }_{z-2} D \left(\beta^{-}\right.$decay $)$