After one $\alpha $ and two $\beta $ emissions
Mass number reduces by $3$
Mass number reduces by $ 4$
Mass number reduces by $6$
Atomic number remains unchanged
Which can pass through $20 \,cm$ thickness of the steel
An element $A$ decays into element $C$ by a two step process :
$A \to B + {\;_2}H{e^4}$
$B \to C + \;2{e^ - }$
Then
When $_{90}T{h^{228}}$ transforms to $_{83}B{i^{212}}$, then the number of the emitted $\alpha$- and $\alpha$- particles is, respectively
In the nuclear reaction: $X(n,\,\alpha ){\,_3}L{i^7}$ the term $X$ will be
A radioactive nucleus emits a beta particle. The parent and daughter nuclei are