Physics - Modern Physics Question with Solution | TestHub

Equivalent reaction can be written as $D\to D_4+2\alpha +{\beta }^{-}+\gamma$

So, mass number of $D_4=$mass number of $D-2\times 4=182-8=174$

Atomic number of $D_4=$atomic number of $D-2\times 2+1=74-4+1=71$

The reaction is 

${}_{74}{}^{182}D\underset{\alpha }{⟶}{}_{72}{}^{178}D_1\underset{{\beta }^{-}}{⟶}{}_{73}{}^{178}D_2\underset{\alpha }{⟶}{}_{71}{}^{174}D_3\underset{\gamma }{\to }{}_{71}{}^{174}D_4$