$\underset{92}{238}U\left(IIIB\right)$ changes to $\underset{90}{284}Th$ by emission of $\alpha$-particle. Daughter element will be in:

Q. A radioactive element belongs to $IIIB$ group; it emits one '$\alpha$' and one $\beta$-particle to form a daughter nuclide. The position of daughter nuclide will be in:

Q. Let us consider emission of $\alpha$-particle from uranium nucleus:
${}_{92}{U}^{235}{\to }_2{He}^4\to$ ${}_{90}{Th}^{231}$
$e=92$ $e=0$ $e=90$
$p=92$ $p=2$ $p=90$
$n=143$ $n=2$ $n=141$
Shortage of two electrons in thorium is due to:

Q. A radioactive nucleus undergoes $\alpha$-emission to form a stable element. What will be the recoil velocity of the daughter nucleus if $v$ is the velocity of $\alpha$ emission?